41286-42-4Relevant academic research and scientific papers
P(III)/P(V)-Catalyzed Methylamination of Arylboronic Acids and Esters: Reductive C-N Coupling with Nitromethane as a Methylamine Surrogate
Li, Gen,Qin, Ziyang,Radosevich, Alexander T.
, p. 16205 - 16210 (2020/10/26)
The direct reductive N-arylation of nitromethane by organophosphorus-catalyzed reductive C-N coupling with arylboronic acid derivatives is reported. This method operates by the action of a small ring organophosphorus-based catalyst (1,2,2,3,4,4-hexamethylphosphetane P-oxide) together with a mild terminal reductant hydrosilane to drive the selective installation of the methylamino group to (hetero)aromatic boronic acids and esters. This method also provides for a unified synthetic approach to isotopically labeled N-methylanilines from various stable isotopologues of nitromethane (i.e., CD3NO2, CH315NO2, and 13CH3NO2), revealing this easy-to-handle compound as a versatile precursor for the direct installation of the methylamino group.
Rational and predictable chemoselective synthesis of oligoamines via Buchwald-Hartwig amination of (hetero)aryl chlorides employing Mor-Dalphos
Tardiff, Bennett J.,McDonald, Robert,Ferguson, Michael J.,Stradiotto, Mark
experimental part, p. 1056 - 1071 (2012/02/15)
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.
Compositions and methods for inhibiting vinyl aromatic monomer polymerization
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, (2008/06/13)
Methods and compositions are provided for inhibiting the polymerization of vinyl aromatic monomers under distillation conditions. The compositions comprise a combination of a phenylenediamine compound and a hydroxylamine compound.
Preparation of N-substituted-N'-phenyl p-phenylenediamines
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, (2008/06/13)
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.
Method for the production of vinyl norbornene
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, (2008/06/13)
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.
Stabilization of unsaturated carboxylic acid esters with mixtures of polyalkylene-amines and arylenediamines
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, (2008/06/13)
A method of inhibiting polymerization of unsaturated carboxylic acid esters and improved unsaturated carboxylic acid ester compositions are described. The method comprises, and the compositions are prepared by, incorporating into the ester composition a combination comprising polyalkyleneamine and arylenediamine of the formula STR1 in which X is hydrogen, chloro, trichloromethyl, trifluoromethyl, nitro, lower alkyl, lower alkoxy or phenoxy, R is hydrogen or alkyl, and R1 is alkyl or phenyl or R and R1 together with the nitrogen atom is a heterocycle selected from the group consisting of pyrrolidinyl, 2,5-dimethyl pyrrolidinyl, piperidino and hexahydro-1H-azepin-1-yl.
