- Synthesis, characterization, and alkyne trimerization catalysis of a heteroleptic two-coordinate FeI complex
-
The synthesis of the first heteroleptic, two-coordinate FeI complex IPr-Fe-N(SiMe3)DIPP (1) (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene; DIPP = 2,6-iPr2-C6H3) is reported. Protonation of the FeII bis(amido) complex Fe[N(SiMe3)DIPP]2 followed by addition of IPr and reduction by potassium graphite in a one-pot reaction results in good yields of 1. The redox activity of 1 and comparison between 1 and its reduction product by 57Fe M?ssbauer spectroscopy are discussed, and the reduction was found to be metal-based rather than ligand-based. The activity of 1 toward the catalytic cyclotrimerization of terminal and internal alkynes is described.
- Lipschutz, Michael I.,Chantarojsiri, Teera,Dong, Yuyang,Tilley, T. Don
-
supporting information
p. 6366 - 6372
(2015/06/02)
-
- Process for synthesizing diisopropylbenzene
-
This invention relates to a process for synthesizing para-diisopropylbenzene utilizing only cumene and propylene as raw materials. This synthesis technique offers the advantage of eliminating benzene as a raw material used in the process. The elimination of benzene is beneficial because it simplifies the process and eliminates the need to purchase and store benzene for use in the synthesis. The elimination of benzene from the synthesis is of particular value since the use of benzene in industrial applications has been under attack on the basis of environmental, safety, and health concerns. The present invention discloses a process for producing para-diisopropylbenzene from cumene and propylene, said process comprising the steps of (1) introducing a feed stream into an alkylation zone wherein said feed stream is comprised of cumene and propylene, and wherein said alkylation zone contains an alkylation catalyst; (2) allowing the cumene and propylene in the feed stream to react together to produce a first mixture of para-diisopropylbenzene and meta-diisopropylbenzene; (3) fractionally distilling the mixture of para-diisopropylbenzene and meta-diisopropylbenzene in a fractional distillation step to separate the meta-diisopropylbenzene from the para-diisopropylbenzene; (4) isomerizing the meta-diisopropylbenzene in the presence of a transalkylation catalyst to produce a second mixture of para-diisopropylbenzene and meta-diisopropylbenzene; (5) recycling the second mixture of para-diisopropylbenzene and meta-diisopropylbenzene recovered from the transalkylation step to the fractional distillation step; and (6) recovering the para-diisopropylbenzene that was separated from the meta-diisopropylbenzene by the fractional distillation step.
- -
-
Page/Page column 5-6
(2008/06/13)
-
- Contributions of enthalpy and entropy factors to isomerization equilibrium of isopropyl- and cyclohexylbenzenes
-
Experimental and theoretical data on the liquid-phase equilibrium of the positional isomerization of isopropyl- and cyclohexylbenzenes are analyzed in detail. Contributions of the enthalpy and entropy factors to the equilibrium constants of the ortho-meta and para-meta transformations are estimated.
- Nesterova,Pimerzin,Krasnykh
-
p. 1884 - 1890
(2007/10/03)
-
- 4-hydroxytetrahydropyran-2-ones and the corresponding dihydroxycarboxylic acid derivatives, salts and esters and a process for their preparation
-
4-Hydroxytetrahydropyran-2-ones and the corresponding dihydroxycarboxylic acid derivatives, salts and esters, process for their preparation, their use as pharmaceuticals, and pharmaceutical preparations and precursors. Compounds of the formula I STR1 and the corresponding open-chain dihydroxycarboxylic acids of the formula II STR2 in which X, Y, R1, R2, R3, R4 and R5 have the meanings indicated, and also their pharmacologically tolerable salts with bases and their pharmacologically tolerable esters, processes for the preparation of these compounds, their use as pharmaceuticals and pharmaceutical preparations are described. In addition, compounds of the formula III STR3 in which R1, R2, R3, R4, R5, X and Y have the meanings indicated are described.
- -
-
-
- Reactions of Hydrogen Chloride with 3-Methyl-1-butyne: Cycloaddition and Rearrangement Reactions via Vinyl Cations
-
3-Methyl-1-butyne was reacted with anhydrous hydrogen chloride in the liquid phase at ambient temperatures.A total of 12 products were identified: three monoadducts (4, 6, 9), three diadducts (5, 7, 10), one substitution product (8), as well as five cycloaddition products having cyclobutane structures (11-15).Model reactions provided evidence for the mode of formation of the reaction products.
- Stammann, Guenter,Griesbaum, Karl
-
p. 598 - 606
(2007/10/02)
-
- The Influence of the Conditions of Synthesis of Aluminosilicates from Tetraethoxysilane and Aluminium Nitrate on Their Activity in the Alkylation Reaction. II. The Influence of the Sequence of Hydrolitic Reactions and the Drying Temperature
-
The paper reports the physical properties and activities, in the alkylation of benzene by propene and butenes, of aluminosilicates synthesised using different sequences of hydrolytic reactions between tetraethoxysilane and an aqueous aluminium nitrate solution and different hydrogel drying temperatures.
- Kolesnikov, I. M.,Grinis, L. M.
-
p. 276 - 277
(2007/10/02)
-