- Palladium-catalyzed reductive coupling of phenols with anilines and amines: efficient conversion of phenolic lignin model monomers and analogues to cyclohexylamines
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Phenols, being readily available from naturally abundant lignins, are important future feedstocks for the renewable production of fuels, chemicals, and energy. Herein, a highly efficient Pd-catalyzed direct coupling of phenolic lignin model monomers and analogues with anilines to give cyclohexylamines using cheap and safe sodium formate as hydrogen donor is described. A variety of secondary and tertiary substituted cyclohexylamines can be synthesized under convenient conditions in moderate to excellent yields.
- Chen, Zhengwang,Zeng, Huiying,Gong, Hang,Wang, Haining,Li, Chao-Jun
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p. 4174 - 4178
(2015/06/25)
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- Rational and predictable chemoselective synthesis of oligoamines via Buchwald-Hartwig amination of (hetero)aryl chlorides employing Mor-Dalphos
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We report a diverse demonstration of synthetically useful chemoselectivity in the synthesis of di-, tri-, and tetraamines (62 examples) by use of Buchwald-Hartwig amination employing a single catalyst system ([Pd(cinnamyl)Cl]2/L1; L1 = N-(2-(di(1-adamantyl)phosphino)phenyl) morpholine, Mor-DalPhos). Competition reactions established the following relative preference of this catalyst system for amine coupling partners: linear primary alkylamines and imines > unhindered electron-rich primary anilines, primary hydrazones, N,N-dialkylhydrazines, and cyclic primary alkylamines > unhindered electron-deficient primary anilines, α-branched acyclic primary alkylamines, hindered electron-rich primary anilines ? cyclic and acyclic secondary dialkylamines, secondary alkyl/aryl and diarylamines, α,α-branched primary alkylamines, and primary amides. The new isomeric ligand N-(4-(di(1-adamantyl)phosphino)phenyl)morpholine (p-Mor-DalPhos, L2) was prepared in 63% yield and was crystallographically characterized; the [Pd(cinnamyl)Cl]2/L2 catalyst system exhibited divergent reactivity. Application of the reactivity trends established for [Pd(cinnamyl)Cl] 2/L1 toward the chemoselective synthesis of di-, tri-, and tetraamines was achieved. Preferential arylation was observed at the primary alkylamine position within 2-(4-aminophenyl)ethylamine with [Pd(cinnamyl)Cl] 2/L1 and 4-chlorotoluene (affording 5a); the alternative regioisomer (5a′) was obtained when using [Pd(cinnamyl)Cl]2/L2. These observations are in keeping with coordination chemistry studies, whereby binding of 2-(4-aminophenyl)ethylamine to the in situ generated [(L1)Pd(p-tolyl)] + fragment occurred via the primary amine moiety, affording the crystallographically characterized adduct [(L1)Pd(p-tolyl)(NH2CH 2CH2(4-C6H4NH2)] +OTf- (7) in 72% yield.
- Tardiff, Bennett J.,McDonald, Robert,Ferguson, Michael J.,Stradiotto, Mark
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experimental part
p. 1056 - 1071
(2012/02/15)
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- Preparation of N-substituted-N'-phenyl p-phenylenediamines
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The present invention relates to a process for the preparation of a N-substituted-N'-phenyl-p-phenylenediamine of the formula: STR1 comprising reacting (a) a mixture of (1) N-phenyl-p-quinoneimine of the formula: STR2 and (2) p-hydroxydiphenylamine in a mole ratio of N-phenyl-p-quinoneimine to p-hydroxydiphenylamine of from 1.5:1 to 1:1.5 with (b) a primary amine of the formula: in the presence of methanol wherein R1 is selected from the group of radicals consisting of alkyls having 1 to 20 carbon atoms, cycloalkyls having 6 to 8 carbon atoms and radicals of the structural formula: STR3 wherein R2 may be the same or different and is independently selected from the group of radicals consisting of hydrogen and an alkyl having 1 carbon atom, R3 is selected from the group of radicals consisting of an alkyl having 1 to 12 carbon atoms and n is an integer of from 0 to 6.
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- 2-Propanol derivatives as corrosion inhibitors
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New composition comprises a functional fluid in contact with ferrous metal and a corrosion inhibiting amount of at least one compound of formula (I) STR1 or a derivative thereof in which R1, R2 and R3 are, independently, hydrogen, a C1 -C15 straight or branched chain alkyl residue, a C5 -C12 cycloalkyl residue, a C6 -C15 aryl residue or C7 -C12 alkaryl residue, and R4 and R5 are, independently, hydrogen, 2-hydroxyethyl or 2-hydroxypropyl with the provisos that (a) R4 and R5 are not simultaneously hydrogen, (b) when R4 and R5 are each --CH2 --CH2 --OH, R1 and R2 are not simultaneously hydrogen and R3 is not a pentyl residue and (c) that polyalkylene and phenol or polycarboxylic ester co-additives are absent; as well as salts thereof. Some of the compounds of formula I are new.
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- Corrosion inhibiting composition
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A composition, in contact with a corrodable metal surface, which composition comprises: (a) an aqueous-based or oil-based system; and (b) as inhibitor for protecting the metal surface against corrosion, at least one compound having the formula I: STR1 as well as salts or partial esters thereof wherein: n is 0 or an integer ranging from 1 to 20, R is a straight or branched chain C4 -C30 alkyl group, optionally interrupted by one, two or three oxygen atoms or substituted by one, two or three hydroxy groups, a C5 -C12 cycloalkyl group, a C6 -C10 aryl group optionally substituted by one, two or three C1 -C12 alkyl groups, or a C7 -C13 aralkyl group which is optionally substituted by a hydroxyl group; R1 is H or a straight- or branched chain C1 -C4 alkyl group; R2 is H, a straight or branched chain C1 -C4 alkyl group or CO2 H; R3 is H, a straight or branched chain C1 -C4 alkyl group, --CH2 CO2 H or --CH2 CH2 CO2 H; R4 is H, a straight or branched chain C1 -C4 alkyl group or CO2 H; R5 is H, a straight or branched chain C1 -C4 alkyl group, CH2 CO2 H or CH2 CH2 CO2 H; provided that at least one group R4 must be CO2 H, with the provisio, that compositions comprising an oil-based system and a compound having the formula STR2 wherein R, R1 and R2 are hydrogen or alkyl radicals, having a total from 10 to 38 C-atoms, are excluded.
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- Preparation of a N-substituted phenylenediamine
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The present invention relates to a process for the preparation of a N-substituted phenylenediamine of the formula: STR1 comprising reacting N-phenylquinoneimine of the formula: STR2 with a primary amine of the formula: wherein the molar ratio of II to III in the reaction mixture ranges from about 1:1 to 1:10; and wherein R is selected from the group of radicals consisting of alkyls having 1 to 20 carbon atoms, cycloalkyls having 6 to 8 carbon atoms and radicals of the structural formula: STR3 wherein R2 may be the same or different and is independently selected from the group of radicals consisting of hydrogen and an alkyl having 1 carbon atom, R3 is selected from the group of radicals consisting of an alkyl having 1 to 12 carbon atoms and n is an integer of from 0 to 6. The present process is characterized by its excellent yields of high purity N-substituted phenylenediamines.
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- Triazole-organodithiophosphate reaction product additives for functional fluids
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New reaction products, useful as additives for functional fluids, are obtained by reacting, at elevated temperature, (A) a triazole having the formula IA or IB: STR1 wherein R7 is hydrogen or a C1 -C20 alkyl residue; R8 and R9 are the same or different and each is C1 -C20 alkyl, C3 -C20 alkenyl, C5 -C12 cycloalkyl, C7 -C13 aralkyl, C6 -C10 aryl or R8 and R9, together with the nitrogen atom to which they are attached, form a 5-, 6- or 7-membered heterocyclic residue or R8 and R9 is each a residue of formula: wherein X is O, S or N(R12), R12 is hydrogen or C1 -C20 alkyl, "alkylene" is a C1 -C12 alkylene residue and n is 0 or an integer from 1 to 6; R10 is hydrogen, C1 -C20 alkyl or C6 -C10 aryl or C7 -C18 alkyl phenyl; and R11 is hydrogen, C1 -C20 alkyl or a residue --CH2 NR8 R9 wherein R8 and R9 have their previous significance; with (B) an organodithiophosphate having the formula: STR2 in which R13 is a C1 -C20 alkyl or C7 -C18 alkyl phenyl or C7 -C13 aralkyl group, M is a metal ion of Group IA, IB, IIA, IIB, VB, VIB, VIIB or VIII of the Periodic System of Elements, and y is the valency of M.
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- Method for the production of vinyl norbornene
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A method for producing vinyl norbornene at a high yield preventing the formation of Diels-Alder reaction by-products which is characterized in that cyclopentadiene and butadiene are reacted in the presence of p-phenylenediamine compounds such as N-isopropyl-N'-phenyl-p-phenylenediamine, N,N'-diphenyl-p-phenylenediamine and the like.
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