WESSJOHANN, LUDGER;MCGAFFIN, GREGORY;MEIJERE, ARMIN DE, SYNTHESIS,(1989) N, C. 359-363
作者:WESSJOHANN, LUDGER、MCGAFFIN, GREGORY、MEIJERE, ARMIN DE
DOI:——
日期:——
Ethyl N-(diphenylmethylene)glycinate as anionic glycine equivalent. Monoalkylation, dialkylation and Michael additions under solid-liquid phase-transfer catalysis
additions to ethylenic and acetylenic acceptors under appropriate solid-liquid phase transfer catalysis conditions. Further transformations of the α-disubstituted ketimines lead to α-alkylated aspartic and glutamic acid derivatives 10, 15, 19 and 26, to bicyclic amino acids or derivatives featuring pyrazolone and isoxazolone moieties 30 and 33, and to α-substituted (E)-3,4-dehydroglutamic acids.
1,4-Addition of (Diphenylmethylene)amine to Acceptor Substituted Olefins. A Versatile Synthesis of Protected β-Amino Acids, Nitriles, and Ketones
作者:Ludger Wessjohann、Gregory Mcgaffin、Armin de Meijere
DOI:10.1055/s-1989-27252
日期:——
(Diphenylmethylene)amine [benzophenone imine, DPMA-H] cleanly reacts with a variety of α,β-unsaturated esters, nitriles, ketones, and aldehydes 1a-q to give Michael type adducts 2a-q, generally, in respectable to excellent yields. Sterically congested and donor-substituted Michael acceptors do not react. The β-amino-substituted products can be further transformed in their protected form, or selectively deprotected under mild conditions, e.g. by catalytic hydrogenation.