Catalytic hydrogenation of methyl esters of some 1h-pyrazoline-3-carboxylic acids
作者:V. A. Gorpinchenko、D. V. Petrovcx、S. S. Lozhkin、E. G. Galkin、V. A. Dokichev
DOI:10.1007/s10593-010-0408-2
日期:2009.10
Hydrogenation over Raney nickel of the methyl ester of 1H-pyrazoline-3-carboxylic acid and also of its 4-phenyl and 5-methoxycarbonyl-substituted analogs, leads respectively to 3-aminopyrrolidin-2-one, its 4-phenyl- and 5-methoxycarbonyl derivatives, predominantly to the trans isomer. Under the same conditions 1-amino-4-methoxycarbonylpyrrolidin-2-one was obtained from 3,4-di(methoxycarbonyl)-1H-pyrazoline
Optically Active 3-Amino-3-Pyrrolidones by Reductive N-N-Bond Cleavage of 1-Pyrazolines Derived from (U)-3- Hydroxybutyric Acid
作者:Annett Bartels、Jürgen Liebscher
DOI:10.1080/00397919908085757
日期:1999.1
Abstract Raney-Ni-catalyzed hydrogenation of 1-pyrazoline-3-carboxylic acid derivatives 3 affords opticallyactive 4-substituted trans-3-amino-2-pyrrolidones 6 as new unnatural α, γ-diaminoacid derivatives by reductive N-N-bond cleavage, ring transformation and retro-aldol reaction.
Enantiodivergent Synthesis of Bis-Spiropyrrolidines via Sequential Interrupted and Completed (3 + 2) Cycloadditions
作者:Egoitz Conde、Iván Rivilla、Amaia Larumbe、Fernando P. Cossío
DOI:10.1021/acs.joc.5b01418
日期:2015.12.4
hydrogenation of the nitro group followed by in situ cyclization. Imines derivedfrom these latter compounds are the precursors of N-metalated azomethineylidesfrom which up to four new chiral centers can be generated via completed (3 + 2) cycloaddition reactions with full regio- and diastereocontrol. Cis- and trans-γ-lactams lead to opposite bis-spiropyrrolidine enantiomers. Therefore, both enantiomeric series