869486-64-6Relevant articles and documents
N -Methylation of ortho -substituted aromatic amines with methanol catalyzed by 2-arylbenzo [d] oxazole NHC-Ir(iii) complexes
Huang, Shuang,Hong, Xi,Cui, He-Zhen,Zhou, Quan,Lin, Yue-Jian,Hou, Xiu-Feng
, p. 5072 - 5082 (2019/04/17)
Seven new chelated cyclometalated Ir complexes of ABON,P, ABON,O, and ABON,C(carbene) based on a rigid and tunable 2-arylbenzo[d]oxazole backbone have been prepared for the N-methylation of amines. Among these three coordinated modes, ABON,C(carbene)-chelated iridium-based catalysts exhibited good performance in the monomethylation of aromatic amines with methanol (MeOH) as the green methylation reagent. The steric-modified synthesis of ABON,C(carbene) complexes was described. The most active ABON,C(carbene) complex with marginal steric hindrance as a catalyst was obtained from the benzoxazole ring without a substituent and methyl group of the benzimidazole ring on the N-heterocyclic carbene (NHC) ligand. A variety of amines including para- and meta-substituted aromatic amines, as well as heterocyclic amines, were formulated as suitable substrates. Importantly, this catalyst considerably promoted the yield of the N-methylation of ortho-substituted aromatic amines. Controlled kinetic experiments and deuterium-labeling reactions of these ortho-substituted amines were conducted under optimized conditions. On the basis of the experimental results, a plausible mechanism was proposed.
Radical cyclization approach to spirocyclohexadienones
Gonzalez-Lopez De Turiso, Felix,Curran, Dennis P.
, p. 151 - 154 (2007/10/03)
(Chemical Equation Presented) Cyclization of an aryl radical at the ipso position of a p-O-aryl-substituted acetamide or benzamide generates oxindoles or quinolones bearing spirocyclohexadienone rings. This versatile reaction is applied to formal synthese
