We report a phosphine‐catalyzed activation of electron‐deficient vinylcyclopropanes (VCPs) to generate an ambident C5 synthon that is poised to undergo consecutive reactions. The utility of the activation is demonstrated in a phosphine‐catalyzed rearrangement of vinylcyclopropylketones to cycloheptenones in good yields with a broad substrate scope. Mechanistic investigations support a stepwise process
Access to α-Hydroxy Amides via a Practical Metal-Free “One-Pot” Tandem Reaction Involving Aerobic C(sp<sup>3</sup>)–H Hydroxylation and C(sp<sup>2</sup>)–C(sp<sup>3</sup>) Cleavage
作者:Xiao Zhang、Yang Yu、Wenjie Li、Lei Shi、Hao Li
DOI:10.1021/acs.joc.2c01839
日期:2022.12.16
A flexible metal-free cascade reactioninvolving aerobic C(sp3)–H hydroxylation and decarbonylation with high regioselectivity and functional group tolerance has been established. Moreover, this indirect hydroxylation approach of N-aryl amides could enable the construction of a wide range of valuable secondary alcohols at α-position of N-aryl amides. It provides a supplementary strategy for direct
Method of preparing a polyamide acid composition for preparing polyimide
申请人:KANEGAFUCHI KAGAKU KOGYO KABUSHIKI KAISHA
公开号:EP0114059A2
公开(公告)日:1984-07-25
A polyamide acid composition for preparing a polyimide which is improved in the stability in a form of solution and can extend the pot life of the composition comprising a solution of a polyamide acid in an organic solvent, the polyamide acid being a precursor of the polyimide, and an N-substituted heterocyclic compound as a chemical treating agent which can lower a rate of conversion of the polyamide acid to the polyimide. The pot life can be extremely extended to give the composition an enough flowability for a long time without reducing the excellent properties such as a heat resistance of the obtained polyimide.