- Convenient synthesis of anionic dinuclear ruthenium(II) complexes [NR2H2][{RuCl(diphosphine)}2(μ-Cl) 3] [diphosphine = 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl, 2,2′-bis(di(p-tolyl)phosphino)-1,1′-binaphthyl, and 1,2-bis(diphenylphosphino)benzene]:
-
We report a practical one-pot synthesis of dialkylammonium salts of anionic dinuclear ruthenium complexes having chelating diphosphine ligands, BINAPs and DPB, with formula of [NEt2H2][{RuCl(diphosphine)}2(μ-Cl) 3] [2a: diphosphine = 2,2′-bis-(diphenylphosphino)-1,1′-binaphthyl; 6a: 2,2′-bis(di(p-tolyl)phosphino)-1,1′-binaphthyl; 8a: 1,2-bis(diphenylphosphino)benzene]. Treatment of cationic ruthenium complexes, [RuCl(η6-p-cymene)(diphosphine)]Cl (4) with a slight excess of NEt2H2Cl (5a) afforded 2a, 6a, and 8a in quantitative yields. Similar reactions with various dialkylammonium salts 5b-f gave the corresponding salts, [NR2H2][{RuCl(diphosphine)}2(μ-Cl) 3]. A one-pot mixture of BINAP or its derivative, [RuCl2(η6-arene)]2, and NR2H2Cl produced salts of the anionic dinuclear complexes which can be applied as catalysts for the asymmetric hydrogenation of ketonic substrates such as acetol and methyl acetoacetate with high activity and high enantioselectivity. The anionic face-sharing bioctahedral structure of these complexes was confirmed by the X-ray analysis of 8a, which has two hydrogen bonds between two NH of the diethylammonium cation and two terminal chloro-ligands.
- Mashima, Kazushi,Nakamura, Tomoko,Matsuo, Yutaka,Tani, Kazuhide
-
-
Read Online
- Method for synthesizing chiral 1,2-diol compound
-
The invention relates to a method for synthesizing a chiral 1,2-diol compound, which comprises the following steps: sequentially adding a cobalt catalyst, a ligand, alpha-hydroxy ketone, an organic solvent and silane into a reaction system at 20-30 DEG C in a nitrogen atmosphere, then stirring the mixture, and carrying out column chromatography separation on the obtained product to obtain the chiral 1,2-diol compound. The high-yield cobalt catalyst in the earth crust is used, meanwhile, cheap silane (PMHS, 500 g/298 yuan) is used as a reducing agent, the asymmetric reduction reaction of alpha-hydroxy ketone can be efficiently achieved under the mild condition, and the chiral 1,2-diol compound with high yield and optical activity is obtained. Moreover, through the creative labor of the inventor, the reaction yield can reach 99%, and meanwhile, the content of the target product in the generated reaction product is 99% (namely, the yield is 99%, 99% ee).
- -
-
Paragraph 0027; 0077-0080
(2021/07/21)
-
- Manganese-Catalyzed Hydroborations with Broad Scope
-
Reductive transformations of easily available oxidized matter are at the heart of synthetic manipulation and chemical valorization. The applications of catalytic hydrofunctionalization benefit from the use of liquid reducing agents and operationally facile setups. Metal-catalyzed hydroborations provide a highly prolific platform for reductive valorizations of stable C=X electrophiles. Here, we report an especially facile, broad-scope reduction of various functions including carbonyls, carboxylates, pyridines, carbodiimides, and carbonates under very mild conditions with the inexpensive pre-catalyst Mn(hmds)2. The reaction could be successfully applied to depolymerizations.
- Ghosh, Pradip,Jacobi von Wangelin, Axel
-
supporting information
p. 16035 - 16043
(2021/06/16)
-
- An alternative stereoselective total synthesis of (-)-pyrenophorol
-
The total synthesis of 16-membered C2–Symmetric dilactone (-)-Pyrenophorol was accomplished starting from commercially available (S)-epoxide prepared by hydrolytic kinetic resolution of (±)–epoxide with key steps of Grignard reaction, Swern oxidation, Wittig reaction and cyclization was achieved by intermolecular Mitsunobu cyclization. The synthesis of (-)-Pyrenophorol accomplished from cheaply available starting material, easily work-up procedures and reduction of cost in industrial process were major advantages of this route.
- Alluraiah, Gurrala,Sreenivasulu, Reddymasu,Chandrasekhar, Choragudi,Raju, Rudraraju Ramesh
-
p. 2738 - 2743
(2018/09/25)
-
- Enantioselective Resolution Copolymerization of Racemic Epoxides and Anhydrides: Efficient Approach for Stereoregular Polyesters and Chiral Epoxides
-
Herein we report an efficient strategy for preparing isotactic polyesters and chiral epoxides via enantioselective resolution copolymerization of racemic terminal epoxides with anhydrides, mediated by enantiopure bimetallic complexes in conjunction with a nucleophilic cocatalyst. The chirality of both the axial linker and the diamine backbones of the ligand are responsible for the chiral induction of this kinetic resolution copolymerization process. The catalyst systems exhibit exceptional levels of enantioselectivity with a kinetic resolution coefficient exceeding 300 for various racemic epoxides, affording highly isotactic copolymers (selectivity factors of more than 300) with a completely alternating structure and low polydispersity index. Most of the produced isotactic polyesters are typical semicrystalline materials with melting temperatures in the range from 77 to 160 °C.
- Li, Jie,Ren, Bai-Hao,Wan, Zhao-Qian,Chen, Shi-Yu,Liu, Ye,Ren, Wei-Min,Lu, Xiao-Bing
-
supporting information
p. 8937 - 8942
(2019/06/11)
-
- Kinetic Resolution of 1,2-Diols via NHC-Catalyzed Site-Selective Esterification
-
A kinetic resolution of 1,2-diols bearing both a secondary and a primary alcohol motif through an N-heterocyclic carbene-catalyzed oxidative acylation reaction has been developed. A site- and enantioselective esterification reaction is involved for this process. Both the monoacylated diols obtained and the remaining enantioenriched 1,2-diols are versatile building blocks for the preparation of functional molecules with proven biological activities.
- Liu, Bin,Yan, Jiekuan,Huang, Ruoyan,Wang, Weihong,Jin, Zhichao,Zanoni, Giuseppe,Zheng, Pengcheng,Yang, Song,Chi, Yonggui Robin
-
supporting information
p. 3447 - 3450
(2018/06/26)
-
- Continuous-Flow Synthesis of (R)-Propylene Carbonate: An Important Intermediate in the Synthesis of Tenofovir
-
(R)-Propylene carbonate is an important intermediate in the synthesis of tenofovir pro-drugs such as tenofovir alafenamide fumarate (TAF) and tenofovir diisoproyl fumarate (TDF). Independent of the pro-drug type, tenofovir presents a chiral secondary hydroxy derivative, which can be obtained directly from (R)-propylene carbonate. Herein, we report our chemo-enzymatic continuous-flow strategy towards (R)-propylene carbonate starting from a very cheap and renewable raw material, glycerol. We were able to synthesize (R)-propylene carbonate in seven continuous-flow steps, starting from glycerol, in good-to-excellent yields (66–93 %) and excellent selectivity (E > 200).
- Suveges, Nicolas S.,Rodriguez, Anderson A.,Diederichs, Carla C.,de Souza, Stefania P.,Le?o, Raquel A. C.,Miranda, Leandro S. M.,Horta, Bruno A. C.,Pedraza, Sérgio F.,de Carvalho, Otavio V.,Pais, Karla C.,Terra, José H. C.,de Souza, Rodrigo O. M. A.
-
p. 2931 - 2938
(2018/06/27)
-
- Water-insoluble ruthenium catalyst composition for use in aqueous hydrogenation reactions
-
The invention relates to a method for converting a precatalyst complex to an active catalyst complex, wherein the precatalyst complex and the active catalyst complex comprise a ruthenium atom and an optically active ligand that is insoluble in water, and the active catalyst complex furthermore comprises a monohydride and a water molecule. The method comprises the steps of providing water as an activation solvent system with a pH value equal or below 2, and solving said precatalyst complex, an acid, and hydrogen therein. The invention further relates to a method for manufacturing a catalyst composition, a method for hydrogenating a substrate molecule and a reaction mixture.
- -
-
Page/Page column 17
(2016/09/26)
-
- SYNTHESIS OF INTERMEDIATES USED IN THE MANUFACTURE OF ANTI-HIV AGENTS
-
The present invention relates to a process of preparing intermediates of Formula (I). The process comprises of reacting compound of Formula (III) with compound of Formula (V) in the presence of a solvent selected from an alcohol, ether or water to form compound of Formula (I) wherein, R1 is selected from –NH2, Cl, Br, NHCOR", wherein R" is alkyl, aryl, Schiff's base of formula N=CHR', wherein R' is alkyl or aryl; R2 is selected from H, alkyl; R3 and R4, each independently is H; R5 and R6, each independently is H, alkyl; R7 is H, alkyl; and R8 is H, alkyl.
- -
-
Page/Page column 18
(2016/11/21)
-
- A method for the synthesis of adenine derivative
-
The invention discloses the technical field of medicines and particularly discloses a new prodrug, namely (R)-9-(2-(phosphonyl methoxyl)propenyl) adenine, a cyclodextrin inclusion compound of the prodrug and a non-toxic and pharmaceutically acceptable salt of the prodrug. The prodrug disclosed by the invention can be metabolized into PMPA in vivo, and has the bioavailability of about 39%, and the bioavailability of the prodrug is better than that of tenofovir disoproxil fumarate (Bis-(POC)-PMPA); and the prodrug has more excellent antiviral activity and better safety compared with the tenofovir disoproxil fumarate.
- -
-
Paragraph 0016; 0021-0022
(2017/04/03)
-
- WATER-INSOLUBLE RUTHENIUM CATALYST COMPOSITION FOR USE IN AQUEOUS HYDROGENATION REACTIONS
-
The invention relates to a method for converting a precatalyst complex to an active catalyst complex, wherein the precatalyst complex and the active catalyst complex comprise a ruthenium atom and an optically active ligand that is insoluble in water, and the active catalyst complex furthermore comprises a monohydride and a water molecule. The method comprises the steps of providing water as an activation solvent system with a pH value equal or below 2, and solving said precatalyst complex, an acid, and hydrogen therein. The invention further relates to a method for manufacturing a catalyst composition, a method for hydrogenating a substrate molecule and a reaction mixture.
- -
-
-
- Nano SiO2-bonded Ru-TsDPEN for catalytic resolution of 1,2-propanediol by two transfer hydrogenation
-
A new strategy was introduced for the catalytic resolution of 1,2-propanediol involving the successive oxidative kinetic resolution and asymmetric hydrogenation by two hydrogen transfer reactions catalyzed by nano SiO2-bonded Ru-TsDPEN [TsDPEN = N-(p-toluenesulfonyl)-1,2-diphenylethylene diamine]-derived catalysts composed of two opposite configurations. The catalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), Fourier-transform infrared spectroscopy (FT-IR), thermogravimetry-derivative thermogravimetry (TG-DTG) analysis, and inductively coupled plasma atomic emission spectrometry (ICP-AES). Results showed that Ru-TsDPEN derived catalysts were successfully grafted on the nano SiO2, affording high catalytic conversions of >99 and 99%, selectivities of 47 and 98% and maximum ee values of >99 and >99% in the two reactions, which were due to the nano SiO2 with Ru-TsDPEN in the reaction system with high dispersion. Additionally, the catalysts exhibited excellent durability and were filtered and reused at least five times without noticeable catalysts deactivations.
- Yue, Chuan-Jun,Gu, Li-Ping,Zhuang, Ya-Feng,Liu, Bao-Liang
-
p. 1207 - 1218
(2015/11/09)
-
- NUCLEOTIDE ANALOGS
-
PROBLEM TO BE SOLVED: To provide, e.g., intermediates for phosphonomethoxy nucleotide analogs, in particular, intermediates suitable for use in efficient oral delivery of such analogs. SOLUTION: Novel compounds are provided that comprise esters of antiviral phosphonomethoxy nucleotide analogs with carbonates and/or carbamates having the structure -OC(R2)2OC(O)X(R)a, The compounds are useful as intermediates for the preparation of antiviral compounds or oligonucleotides, or are useful for administration directly to patients for antiviral therapy or prophylaxis (R2 is as described in the specifications ). COPYRIGHT: (C)2015,JPOandINPIT
- -
-
Paragraph 0166; 0167; 0172
(2018/11/22)
-
- Selective hydrogenation of lactic acid to 1,2-propanediol over highly active ruthenium-molybdenum oxide catalysts
-
Modification of Ru/C with a small amount of MoOx (Ru-MoOx/C) enhanced the catalytic activity in the hydrogenation of L-lactic acid to form 1,2-propanediol and maintained high selectivity. The turnover frequency based on the amount of Ru over the optimized Ru-MoOx/C catalyst (Mo/Ru molar ratio=1:16) was 114 h-1 at 393 K, which was about 4 times higher than that over Ru/C. The same effect of MoOx was obtained over Ru-MoOx/SiO2, although Ru-MoOx/SiO2 showed slightly lower activity than that of Ru-MoOx/C. Ru-MoOx/C achieved a high yield of 95 % in 18 h at 393 K and was applicable to various carboxylic acids to provide the corresponding alcohols in high yields. Modification with MoOx also brought about suppression of racemization and (S)-1,2-propanediol was obtained in high enantiomeric excess at 353 K. Based on kinetic analysis and characterization data, such as XRD, TEM, CO adsorption by a volumetric method, FTIR spectroscopy, and X-ray absorption spectroscopy, for Ru-MoOx/C and Ru-MoOx/SiO2, the catalyst structure and reaction mechanism are proposed.
- Takeda, Yasuyuki,Shoji, Tomohiro,Watanabe, Hideo,Tamura, Masazumi,Nakagawa, Yoshinao,Okumura, Kazu,Tomishige, Keiichi
-
p. 1170 - 1178
(2015/04/22)
-
- Water-insoluble Ruthenium catalyst composition for use in aqueous hydrogenation reactions
-
The invention relates to a method for converting a precatalyst complex to an active catalyst complex, wherein the precatalyst complex and the active catalyst complex comprise a ruthenium atom and an optically active ligand that is insoluble in water, and the active catalyst complex furthermore comprises a monohydride and a water molecule. The method comprises the steps of providing water as an activation solvent system with a pH value equal or below 2, and solving said precatalyst complex, an acid, and hydrogen therein. The invention further relates to a method for manufacturing a catalyst composition, a method for hydrogenating a substrate molecule and a reaction mixture.
- -
-
-
- Asymmetric hydrolytic kinetic resolution with recyclable polymeric Co(iii)-salen complexes: A practical strategy in the preparation of (S)-metoprolol, (S)-toliprolol and (S)-alprenolol: Computational rationale for enantioselectivity
-
A series of chiral polymeric Co(iii)-salen complexes based on a number of achiral and chiral linkers were synthesized and their catalytic performances were assessed in the asymmetric hydrolytic kinetic resolution of terminal epoxides. The effects of the linker were judiciously studied and it was found that in the case of the chiral BINOL-based polymeric salen complex 1, there was an enrichment in catalyst reactivity and enantioselectivity of the unreacted epoxide, particularly in the case of short as well as long chain aliphatic epoxides. Good isolated yields of the unreacted epoxide (up to 46% compared to 50% theoretical yield) along with high enantioselectivity (up to 99%) were obtained in most cases using catalyst 1. Further studies showed that catalyst 1 could retain its catalytic activity for six cycles under the present reaction conditions without any significant loss in activity or enantioselectivity. To show the practical applicability of the above synthesized catalyst we have synthesised some potent chiral β-blockers in moderate yield and high enantioselectivity using complex 1. The DFT (M06-L/6-31+G??//ONIOM(B3LYP/6-31G?:STO-3G)) calculations revealed that the chiral BINOL linker influences the enantioselectivity achieved with Co(iii)-salen complexes. Further, the transition state calculations show that the R-BINOL linker with the (S,S)-Co(iii)-salen complex is energetically preferred over the corresponding S-BINOL linker with the (S,S)-Co(iii)-salen complex for the HKR of 1,2-epoxyhexane. The role of non-covalent C-H?π interactions and steric effects has been discussed to control the HKR reaction of 1,2-epoxyhexane.
- Roy, Tamal,Barik, Sunirmal,Kumar, Manish,Kureshy, Rukhsana I.,Ganguly, Bishwajit,Khan, Noor-Ul H.,Abdi, Sayed H. R.,Bajaj, Hari C.
-
p. 3899 - 3908
(2015/02/19)
-
- Propane-1,2-diols from dilactides, oligolactides, or poly-L-lactic acid (PLLA): From plastic waste to chiral bulk chemicals
-
The preparation of racemic or enantioenriched propane-1,2-diol from dilactides, oligolactides, or poly-L-lactic acid (PLLA) is described. The transformation is carried out as tandem reactions in MeOH, covering hydrolysis and subsequent hydrogenation by using copper chromite as a catalyst. The starting material present undesired side products of the PLLA synthesis or PLLA waste. Copyright
- Shuklov, Ivan A.,Dubrovina, Natalia V.,Schulze, Joachim,Tietz, Wolfgang,Kuehlein, Klaus,Boerner, Armin
-
p. 957 - 960
(2014/02/14)
-
- PRODUCTION OF OPTICALLY PURE PROPANE-1,2-DIOL
-
A method for producing optically pure propane-1,2-diol, including the method steps: a. hydrogenation of lactides, metal-catalysed heterogenous catalysis being carried out in the presence of hydrogen, a crude product containing propane-1,2-diol being produced, and b. dynamic, kinetic racemate resolution, propane-1,2-diol of an optical purity in the range of ≧99% e.e. being produced.
- -
-
Paragraph 0042; 0043; 0044
(2014/08/07)
-
- Immobilized Aspergillus niger epoxide hydrolases: Cost-effective biocatalysts for the prepation of enantiopure styrene oxide, propylene oxide and epichlorohydrin
-
This study aimed to prepare robust immobilized epoxide hydrolase (EH) preparations for asymmetric hydrolysis of racemic epoxides such as styrene oxide, propylene oxide and epichlorohydrin. For this purpose, Aspergillus niger EH was immobilized onto Lewatit VP OC 1600 support by adsorption, modified Florisil and Eupergit C supports by covalently. The suitability of the supports was examined for protein binding capacity and rate of racemic styrene oxide hydrolysis. The protein-activity recovery yields were 75-85%, 82-78% and 90-75%, respectively for EH immobilized onto Lewatit VP OC 1600, modified Florisil and Eupergit C supports. All A. niger EH preparations catalyzed preferentially hydrolysis of (R)-epoxides. Although enantiomeric excess values of all the tested epoxides were 99%, the highest enantiopure epoxide yields were obtained as 48% for (S)-styrene oxide by the immobilized EHs onto modified Florisil and Eupergit C. The highest diol yield was obtained as 78% for 3-chloro-1,2-propanediol, however, its enantiomeric excess value was 28.2%. Enantioselectivity of A. niger EH was improved with the preparation of mentioned immobilized forms. The highest enantioselectivity value was obtained as 95 toward styrene oxide by A. niger EH immobilized onto modified Florisil . The results of reusability studies show that the immobilized EH preparations offer feasible potentials for the preparation of enantiopure epoxides than that of free form.
- Yildirim, Deniz,Tuekel, S. Seyhan,Alptekin, Oezlem,Alagoez, Dilek
-
-
- Tailoring the window sizes to control the local concentration and activity of (salen)Co catalysts in plugged nanochannels of SBA-15 materials
-
Ship shape! Chiral (salen)CoIII complexes (spheres) inside plugged nanochannels of SBA-15 materials is achieved using a ship-in-a-bottle synthesis technique. The local concentration of the metal complexes and the catalytic activity (such as the hydrolytic kinetic resolution of 1,2-epoxyalkanes; see scheme) showed a strong dependence on the size of the window. Copyright
- Shakeri, Mozaffar,Klein Gebbink, Robertus J. M.,De Jongh, Petra E.,De Jong, Krijn P.
-
p. 10854 - 10857
(2013/10/22)
-
- Stereoselective total synthesis of 4-ketoclonostachydiol
-
An efficient stereoselective total synthesis of the bioactive 14-membered natural macrocyclic bislactone 4-ketoclonostachydiol is described. The strategy involves a Jacobsen's hydrolytic kinetic resolution (HKR), epoxide opening, MacMillan α-hydroxylation, Horner-Wadsworth-Emmons olefination, a Grignard reaction, and Hoveyda-Grubbs-II-catalyzed ring-closing metathesis (RCM) as key steps.
- Rajaram, Singanaboina,Ramulu, Udugu,Ramesh, Dasari,Prabhakar, Peddikotla,Venkateswarlu, Yenamandra
-
p. 2115 - 2123
(2013/12/04)
-
- Catalytic hydrogenation of esters. Development of an efficient catalyst and processes for synthesising (R)-1,2-propanediol and 2-(l-Menthoxy)ethanol
-
A ruthenium catalyst for the reduction of esters by hydrogenation has been developed. Processes for the hydrogenation of esters have also been developed for (R)-1,2-propanediol and 2-(l-menthoxy)ethanol. The catalyst shows good catalytic activity for the hydrogenation of esters in methanol. Methyl lactate was reduced at 30 °C and gave turnover numbers (TON) up to 4000. The optical purity of the (R)-1,2-propanediol made by the hydrogenation of methyl (R)-lactate was higher than that via the asymmetric hydrogenation of hydroxyacetone. A hydrogenation process to replace the lithium aluminum hydride (LAH) reduction used in the production of 2-(l-menthoxy)ethanol was developed.
- Kuriyama, Wataru,Matsumoto, Takaji,Ogata, Osamu,Ino, Yasunori,Aoki, Kunimori,Tanaka, Shigeru,Ishida, Kenya,Kobayashi, Tohru,Sayo, Noboru,Saito, Takao
-
experimental part
p. 166 - 171
(2012/05/20)
-
- Mono-etherification of racemic propane-1,2-diol by a tin(II) bromide catalyzed reaction with diazofluorene and a study of the Pseudomonas cepacia lipase catalyzed acetylation of the mono-ethers
-
The tin(II) bromide catalyzed reaction of diazofluorene with racemic propane-1,2-diol in 1,2-dimethoxymethane gave the 1- and 2-monoethers in similar amounts. After tritylation of the 2-ether, 2-(9H-fluoren-9-yloxy)-1- triphenylmethyloxypropane and 1-(9H-fluoren-9-yloxy)propan-2-ol were obtained in pure form. The enantiomeric 1-fluorenyl ethers were resolved by kinetic resolution by transacetylation with the help of Pseudomonas cepacia lipase and both enantiomers of the propane-1,2-diol were obtained after deprotection. The racemic 2-(9H-fluoren-9-yloxy)propan-1-ol was obtained after de-triphenylmethylation. However, transacetylation onto this alcohol under identical conditions to those used for the 1-fluorenyl ether showed no enantioselectivity.
- Petursson, Sigthor,Jonsdottir, Sigridur
-
experimental part
p. 157 - 163
(2012/06/04)
-
- Ruthenium- and lipase-catalyzed inversion of l-lactates
-
The ruthenium catalyzed inversion of l-lactic acid esters in the presence of Novozym 435 is described which give d-lactates in good yields and with >99% ee. 2012 Elsevier Ltd. All rights reserved.
- Shuklov, Ivan A.,Dubrovina, Natalia V.,Schulze, Joachim,Tietz, Wolfgang,Kühlein, Klaus,B?rner, Armin
-
p. 6326 - 6328
(2013/01/15)
-
- Chiral ruthenabicyclic complexes: Precatalysts for rapid, enantioselective, and wide-scope hydrogenation of ketones
-
A novel ruthenabicyclic complex with base shows excellent catalytic activity in the asymmetric hydrogenation of ketones. The turnover frequency of the hydrogenation of acetophenone reaches about 35 000 min-1 in the best case, affording 1-phenylethanol in >99% ee. Several aliphatic and base-labile ketones are smoothly converted to the corresponding alcohols in high enantioselectivity. The catalytic cycle for this hydrogenation, in which the ruthenabicyclic structure of the catalyst is maintained, is proposed on the basis of the deuteration experiment and spectroscopic analysis data.
- Matsumura, Kazuhiko,Arai, Noriyoshi,Hori, Kiyoto,Saito, Takao,Sayo, Noboru,Ohkuma, Takeshi
-
supporting information; experimental part
p. 10696 - 10699
(2011/09/15)
-
- NOVEL RUTHENIUM CARBONYL COMPLEX HAVING TRIDENTATE LIGAND, ITS PRODUCTION METHOD AND USE
-
The present invention relates to a ruthenium carbonyl complex that is represented by the following Formula (1): [in-line-formulae]RuXY(CO)(L)??(1)[/in-line-formulae](in the Formula (1), X and Y, which may be the same or different from each other, represent an anionic ligand and L represents a tridentate aminodiphosphine ligand which has two phosphino groups and a —NH— group), its production method, and a method for production of alcohols by hydrogenation-reduction of ketones, esters, and lactones using the complex as a catalyst. The ruthenium carbonyl complex of the invention has a high catalytic activity and it can be easily prepared and handled.
- -
-
Page/Page column 10-11
(2011/10/12)
-
- Resolution of a racemic 1,2-diol using triphenylmethyl protection of the primary hydroxyl group and Mucor miehei lipase (Lipozyme) for the kinetic resolution
-
The triphenylmethyl group gives very simple access to the 1-protection of 1,2-diol as exemplified by racemic propane-1,2-diol. This group has, however, been shown to be incompatible with lipases commonly used for the resolution of alcohols. This turned out to be the case for Pseudomonas cepacia lipase, which we have used in our earlier work. Lipozyme, a Mucor miehei lipase, best known for 1,3-selectivity with glycerol is, however, shown to catalyze transacetylation onto the secondary hydroxyl group next to a triphenylmethoxy group. The transacetylation is completely enantioselective for the (R)-enantiomer giving a very simple method for the resolution of this type of 1,2-diol enantiomer.
- Petursson, Sigthor,Jonsdottir, Sigridur
-
experimental part
p. 1809 - 1812
(2012/01/13)
-
- Asymmetric ring opening of terminal epoxides via kinetic resolution catalyzed by chiral (salen)Co mixture
-
The highly enantioselective hydrolytic kinetic resolution (HKR) of racemic terminal epoxides by bimetallic chiral (salen)Co and (salen)Co(III)-OAc mixture provides a simple and effective method for the synthesis of enantiomerically enriched terminal epoxides (ee > 99%) and diols. At the equimolar amounts of bimetallic chiral (salen)Co and (salen)Co(II)-OAc, the catalytic activity increases more than two times in comparison with (salen)Co(III)-OAc used alone. The mixed catalytic system can be recycled and reused. No significant loss of catalytic activity was observed after three runs.
- Jiang, Chengjun
-
experimental part
p. 691 - 696
(2011/11/30)
-
- METHOD FOR PRODUCING ALCOHOL BY HYDROGENATING LACTONE AND CARBOXYLIC ACID ESTER IN LIQUID PHASE
-
Disclosed is a method for producing an alcohol from a lactone or a carboxylic acid ester, which enables to produce an alcohol from a lactone or a carboxylic acid ester under relatively mild conditions with high yield and high catalytic efficiency. This method also enables to produce an optically active alcohol from an optically active lactone or an optically active carboxylic acid ester. Specifically disclosed is a method for producing an alcohol by hydrogen reducing a lactone or a carboxylic acid ester in the presence of a catalyst containing ruthenium and a phosphine compound represented by the following general formula (1): wherein R1 represents a spacer; R2, R3, R4, R5, R6 and R7 independently represent a hydrogen atom, an alkyl group having 1-12 carbon atoms, an aryl group or a heterocyclic group; and R8, R9, R10, R11, R12 and R13 independently represent an alkyl group having 1-12 carbon atoms, an aryl group or a heterocyclic group.
- -
-
Page/Page column 17
(2010/01/29)
-
- ALCOHOL PRODUCTION METHOD BY REDUCING ESTER OF LACTONE WITH HYDROGEN
-
Provided is an alcohol production method comprising the step of reducing an ester or a lactone with hydrogen to produce a corresponding alcohol without addition of a base compound by using, as a catalyst, a ruthenium complex represented by the following general formula (1): [in-line-formulae]RuH(X)(L1)(L2)n ??(1)[/in-line-formulae] wherein X represents a monovalent anionic ligand,L1 represents a tetradentate ligand having at least one coordinating phosphino group and at least one coordinating amino group or a bidentate aminophosphine ligand having one coordinating phosphino group and one coordinating amino group, andL2 represents a bidentate aminophosphine ligand having one coordinating phosphino group and one coordinating amino group, provided thatn is 0 when L1 is the tetradentate ligand, and n is 1 when L1 is the bidentate aminophosphine ligand.
- -
-
Page/Page column 15
(2010/04/23)
-
- METHOD FOR FRACTIONATING STEREOISOMERIC COMPOUNDS
-
The present invention relates to a method for fractionating stereoisomeric compounds which have at least one alcohol and/or amino group.
- -
-
Page/Page column 10-11
(2009/02/11)
-
- Highly regioselective primary etherification of racemic propane-1,2-diol by the tin(II) bromide-catalyzed reaction with diazo[bis(4-methoxyphenyl)]methane and the resolution of enantiomers with the help of Pseudomonas cepacia lipase
-
The tin(II) bromide-catalyzed reaction of diazo[bis(4-methoxyphenyl)]methane with racemic propane-1,2-diol in 1,2-dimethoxymethane resulted in the highly regioselective etherification of the primary hydroxyl group. After tritylation of the minor 2-ether,
- Petursson, Sigthor
-
experimental part
p. 887 - 891
(2009/09/25)
-
- Studies on the biodegradation of fosfomycin: Growth of Rhizobium huakuii PMY1 on possible intermediates synthesised chemically
-
The first step of the mineralisation of fosfomycin by R. huakuii PMY1 is hydrolytic ring opening with the formation of (1R,2R)-1,2- dihydroxypropylphosphonic acid. This phosphonic acid and its three stereoisomers were synthesised by chemical means and tes
- McGrath, John W.,Hammerschmidt, Friedrich,Preusser, Werner,Quinn, John P.,Schweifer, Anna
-
experimental part
p. 1944 - 1953
(2009/06/28)
-
- Atorvastatin calcium propylene glycol solvates
-
Atorvastatin calcium propylene glycol solvates and processes to prepare these novel solvates which are particularly useful and suitable for pharmaceutical applications.
- -
-
Page/Page column 6
(2008/12/07)
-
- Stereoselective functionalisation of SuperQuat enamides: asymmetric synthesis of homochiral 1,2-diols and α-benzyloxy carbonyl compounds
-
Homochiral (E)- and (Z)-enamides derived from SuperQuat (S)-4-phenyl-5,5-dimethyl-oxazolidin-2-one undergo highly diastereoselective epoxidation upon treatment with dimethyldioxirane. Subsequent epoxide opening with meta-chlorobenzoic acid proceeds via a stereoselective SN1-type process, with retention of configuration, to give the corresponding 1′-m-chlorobenzoyl-2′-hydroxy derivatives. Treatment of the SuperQuat enamides with mCPBA effects this two-step transformation in one pot. Reductive cleavage of the isolated 1′-m-chlorobenzoyl-2′-hydroxy derivatives (≥96% de) generates homochiral 1,2-diols in ≥96% ee. Alternatively, regioselective lithiation of the enamide at C(1′) with tBuLi followed by reaction with an aromatic aldehyde and in situ O-benzylation generates a 1′-(benzyloxy-aryl-methyl) substituted enamide with high diastereoselectivity. Subsequent oxidative cleavage of the enamide C{double bond, long}C bond with NaIO4/RuCl3 followed by methanolysis of the resultant N-acyl fragment furnishes an O-benzyl protected α-hydroxy methyl ester in high ee.
- Aciro, Caroline,Davies, Stephen G.,Garner, A. Christopher,Ishii, Yutaka,Key, Min-Suk,Ling, Kenneth B.,Prasad, R. Shyam,Roberts, Paul M.,Rodriguez-Solla, Humberto,O'Leary-Steele, Catherine,Russell, Angela J.,Sanganee, Hitesh J.,Savory, Edward D.,Smith, Andrew D.,Thomson, James E.
-
p. 9320 - 9344
(2008/12/22)
-
- Asymmetric hydrogenation of α-hydroxy ketones catalyzed by MsDPEN-Cp*Ir(III) complex
-
Asymmetric hydrogenation of a series of α-hydroxy aromatic ketones in methanol catalyzed by Cp*Ir(OTf)(MsDPEN) (MsDPEN = N-(methanesulfonyl)-1, 2-diphenylethylenediamine) affords the 1-aryl-1,2-ethanediols in up to 99% ee. The reaction can be conducted with a substrate-to-catalyst molar ratio at high as 6000 under 10 atm of H2-1-Hydroxy-2-propanone is also hydrogenated with high enantioselectivity.
- Ohkuma, Takeshi,Utsumi, Noriyuki,Watanabe, Masahito,Tsutsumi, Kunihiko,Arai, Noriyoshi,Murata, Kunihiko
-
p. 2564 - 2567
(2008/02/05)
-
- PROCESS FOR PRODUCTION OF OPTICALLY ACTIVE ALCOHOLS
-
A ruthenium complex RuCl[(S,S)-Tsdpen](p-cymene) represented by a formula below and a ketone compound are placed in a polar solvent, and the resulting mixture is mixed under pressurized hydrogen to hydrogenate the ketone compound and to thereby produce an optically active alcohol:
- -
-
Page/Page column 13
(2008/06/13)
-
- RCM mediated synthesis of macrosphelides I and G
-
The total synthesis of 16-membered macrolides, macraosphelides I and G, has been achieved starting from ethyl-(S)-lactate and (S)-malic acid. A combination of Jacobsen's hydrolytic kinetic resolution and Sharpless epoxidation is used for the creation of two stereogenic centres, while Yamaguchi esterification and ring-closing metathesis strategies were used for the construction of the lactone ring.
- Sharma, Gangavaram V.M.,Veera Babu, Kagita
-
p. 2175 - 2184
(2008/02/11)
-
- "Cassette" in situ enzymatic screening identifies complementary chiral scaffolds for hydrolytic kinetic resolution across a range of epoxides
-
(Figure Presented) Put the cassette in: An in situ enzymatic screen can give real-time estimates of the sense and magnitude of enantioselectivity across more than one substrate. Screening identified CoIII-salen catalysts with β-pinene- and α-naphthylalanine-derived chiral scaffolds with broad, yet complementary, substrate specificities. ADH = alcohol dehydrogenase, HL = horse liver, LK = Lactobacillus kefir, salen = (salicylidene) ethylenediamine.
- Dey, Sangeeta,Powell, Douglas R.,Hu, Chunhua,Berkowitz, David B.
-
p. 7010 - 7014
(2008/09/17)
-
- A new dinuclear chiral salen complexes for asymmetric ring opening and closing reactions: Synthesis of valuable chiral intermediates
-
A new dinuclear chiral Co(salen) complexes bearing group 13 metals have been synthesized and characterized. The easily prepared complexes exhibited very high catalytic reactivity and enantioselectivity for the asymmetric ring opening of epoxides with H2O, chloride ions and carboxylic acids and consequently provide enantiomerically enriched terminal epoxides (>99% ee). It also catalyzes the asymmetric cyclization of ring opened product, to prepare optically pure terminal epoxides in one step. The homogeneous dinuclear chiral Co(salen) have been covalently immobilized on MCM-41. The potential benefits of heterogenization include facilitation of catalyst separation and recyclability requiring very simple techniques. The system described is very efficient.
- Thakur, Santosh Singh,Chen, Shu-Wei,Li, Wenji,Shin, Chang-Kyo,Kim, Seong-Jin,Koo, Yoon-Mo,Kim, Geon-Joong
-
p. 1862 - 1872
(2007/10/03)
-
- A simple and efficient approach to 1,3-polyols: Application to the synthesis of cryptocarya diacetate
-
A highly enantio- and stereoselective synthetic strategy for both syn-and anti-1,3-polyols has been developed. The sequence involves iterative Jacobsen's hydrolytic kinetic resolution (HKR), diastereoselective iodine-induced electrophilic cyclization, and ring-closing metathesis (RCM). This protocol has subsequently been utilized for the synthesis of cryptocarya diacetate, a natural product with broad range of biological activity.
- Kumar, Pradeep,Gupta, Priti,Vasudeva Naidu
-
p. 1397 - 1402
(2008/01/27)
-
- Synthesis of optically pure terminal epoxide and 1,2-diol via hydrolytic kinetic resolution catalyzed by new heterometallic salen complexes
-
The inactive chiral (salen)Co complex is easily activated by InCl 3 and TlCl3 Lewis acids by forming heterometallic salen complexes. These complexes show very high catalytic activity for the synthesis of enantiomerically enriched terminal epoxides (>99% ee) and 1,2-diols simultaneously via hydrolytic kinetic resolution. Strong synergistic effects of different Lewis acids, Co-In and Co-Tl, were exhibited in the catalytic process. The system described is very simple and efficient. Copyright Taylor & Francis Group, LLC.
- Thakur, Santosh Singh,Chen, Shu-Wei,Li, Wenji,Shin, Chang-Kyo,Koo, Yoon-Mo,Kim, Geon-Joong
-
p. 2371 - 2383
(2007/10/03)
-
- Stereoselective synthesis of (+)-diplodialides-B, C and a formal synthesis of (+)-diplodialide-A by ring-closing metathesis approach
-
Stereoselective synthesis of diplodialides-B and C and the formal synthesis of diplodialide-A are reported. A combination of Jacobsen's hydrolytic kinetic resolution and Sharpless epoxidation is used for the creation of two stereogenic centers, while a ring-closing metathesis strategy was used for the construction of the lactone ring.
- Sharma,Reddy, K. Laxmi
-
p. 3197 - 3202
(2007/10/03)
-
- Double-cuvette ISES: In situ estimation of enantioselectivity and relative rate for catalyst screening
-
Described is a new method for the screening of an array of catalysts, in situ, to estimate enantioselectivity and relative rates. We term this approach "double-cuvette ISES (in situ enzymatic screening)". The Co(III)-salen mediated hydrolytic kinetic resolution (HKR) of (±)-propylene oxide is used as a model reaction to demonstrate proof of principle. In two parallel cuvettes, a lower CHCl3-based organic layer is loaded with the epoxide and the chiral salen catalyst. Aqueous reporting layers, containing distinct "reporting enzymes" and their nicotinamide cofactors, are layered above the organic layers. The 1,2-propanediol enantiomers formed by the chiral catalyst diffuse into the aqueous layer and are oxidized there by the reporting enzymes at rates dependent upon the diol concentration, the R:S ratio of the diol, and the enantioselectivity of the reporting enzymes. A focused chiral salen library was constructed from seven chiral 1,2-diamines, derived from amino acid, terpenoid, and carbohydrates skeletons, and seven salicylaldehyde derivatives. Double-cuvette ISES identified a couple of interesting combinatorial hits in this salen array, wherein either the sense or magnitude of enantioselection for a given chiral diamine depends significantly upon the choice of "salicylaldehyde" partner. A comparison of predicted ee's and relative rates using this new screening tool with those independently measured is provided. Copyright
- Dey, Sangeeta,Karukurichi, Kannan R.,Shen, Weijun,Berkowitz, David B.
-
p. 8610 - 8611
(2007/10/03)
-
- PROCESS FOR THE HYDROGENATION OF ESTERS OF ALPHA-SUBSTITUTED CARBOXYLIC ACIDS
-
There is provided a process for the hydrogenation of esters of alpha-substituted carboxylic acids which comprises reacting an ester of an alpha-substituted carboxylic acid with hydrogen in the presence of a catalyst under substantially homogeneous supercritical conditions. Preferably, the ester of an alpha-substituted carboxylic acids is an ester of formula (1): wherein: R1 and R2are each independently an optionally substituted hydrocarbyl group or an optionally substituted heterocyclic group; and Y is a heteroatom or an optionally substituted heteroatom group. More preferably, the ester of an alpha-substituted is carboxylic acids is an ester of formula (2): wherein: R3 is an optionally substituted hydrocarbyl group or an optionally substituted heterocyclic group; R4and R5 are each independently hydrogen, an optionally substituted hydrocarbyl group or an optionally substituted heterocyclic group; Y is a heteroatom or an optionally substituted heteroatom group; Q is a functional group; and n 1. Most preferably, the ester of an alpha-substituted carboxylic acids is an ester of formula (3): wherein: R3 and R6 are each independently an optionally substituted hydrocarbyl group or an optionally substituted heterocyclic group; R4 and R5 are each independently hydrogen, an optionally substituted hydrocarbyl group or an optionally substituted heterocyclic group; Y is a heteroatom or an optionally substituted heteroatom group; and n 1.
- -
-
Page/Page column 12-13
(2008/06/13)
-
- Fluorous biphasic hydrolytic kinetic resolution of terminal epoxides
-
Although application of light-fluorous techniques facilitates the isolation of reaction products from the hydrolytic kinetic resolution (HKR) of terminal epoxides catalysed by cobalt complexes of salen ligands, the extension of the original fluorous biphasic approach to this reaction is far from being a trivial exercise. The nature of the counter anion has a dramatic effect on the catalytic activity of heavily fluorinated chiral (salen) cobalt(III) complexes. Excellent enantioselectivities are obtained in the fluorous biphasic HKR of 1,2-hexene oxide when fluorinated anions are introduced (e.e.s up to 99% both for the diol and the epoxide), with C8F17COO- affording reaction rates even higher than those observed with non-fluorous systems.
- Shepperson, Ian,Cavazzini, Marco,Pozzi, Gianluca,Quici, Silvio
-
p. 175 - 180
(2007/10/03)
-
- SYNPHOS: A new atropisomeric diphosphine ligand. From laboratory-scale synthesis to scale-up development
-
A new optically active diphosphine ligand, [(5,6),(5′,6′)-bis(ethylenedioxy)biphenyl.2,2′-diyl]bis (diphenylphosphine) (SYNPHOS) has been synthesized. Laboratory-scale synthesis and scale-up development of this ligand are described herein. This new atropisomeric diphosphine was also used in ruthenium-catalyzed asymmetric hydrogenation.
- Duprat De Paule, Sebastien,Jeulin, Severine,Ratovelomanana-Vidal, Virginie,Genet, Jean-Pierre,Champion, Nicolas,Deschaux, Gilles,Dellis, Philippe
-
p. 399 - 406
(2013/09/06)
-
- AlEt3-promoted eliminative ring-opening of β-hydroxy epoxides: Highly stereoselective synthesis of terminal α-hydroxy olefins
-
AlEt3-promoted eliminative ring-opening of β-epoxy alcohols leading to α-hydroxy olefins is reported. This eliminative ring-opening reaction is shown to be highly stereoselective, thus providing an alternative asymmetric synthesis for α-hydroxy olefins.
- Wang, Fei,Wang, Shao Hua,Tu, Yong Qiang,Ren, Shi Kuo
-
p. 2189 - 2193
(2007/10/03)
-
- Chiral Co(III)(salen)-catalysed hydrolytic kinetic resolution of racemic epoxides in ionic liquids
-
In the chiral Co(III)(salen)-catalysed HKR of racemic epoxides, in the presence of ionic liquids, Co(II)(salen) complex is oxidised without acetic acid to catalytically active Co(III)(salen) complex during reaction and, moreover, this oxidation state is stabilised against reduction to Co(II) complex which enables the reuse of the recovered catalyst for consecutive reactions without extra reoxidation.
- Oh, Chun Rim,Choo, Dong Joon,Shim, Woo Ho,Lee, Dong Hoon,Roh, Eun Joo,Lee, Sang-Gi,Song, Choong Eui
-
p. 1100 - 1101
(2007/10/03)
-
- Nucleotide analog composition and synthesis method
-
The invention relates to a composition comprising a solution of 9-[2-(phosphono-methoxy)propyl]adenine (PMPA) at a pH of about 2.7 ― 3.5 wherein the solution has less than about 0.1 g/ml (R, S)-PMPA and wherein about 90 ― 94 % of the PMPA is in the (R) configuration.
- -
-
-