Functionalised pyrrolidinones derived from (S)-pyroglutamic acid by cycloaddition reactions
摘要:
The alpha,beta-unsaturated bicyclic lactams 3a,c, prepared from (S)-pyroglutamic acid, are useful substrates for cycloaddition reactions, giving excellent regio-and diastereocontrol; however, lactam 3c has very superior reactivity with several dienes and dipoles under mild reaction conditions. (C) 1997 Elsevier Science Ltd.
Functionalised pyrrolidinones derived from (S)-pyroglutamic acid by cycloaddition reactions
摘要:
The alpha,beta-unsaturated bicyclic lactams 3a,c, prepared from (S)-pyroglutamic acid, are useful substrates for cycloaddition reactions, giving excellent regio-and diastereocontrol; however, lactam 3c has very superior reactivity with several dienes and dipoles under mild reaction conditions. (C) 1997 Elsevier Science Ltd.
A concise approach to functionalised, homochiral pyrrolidinones
作者:Mark J Bamford、Mark Beard、David T Cherry、Mark G Moloney
DOI:10.1016/0957-4166(95)00007-c
日期:1995.2
Acylation of O,N-acetal 1 gives excellent yields of the C-7 substituted products 2a,b. Alkylation of 2a under mild conditions gives high yields of the exo- 3 and endo- 4 substituted products in varying ratios, depending on the alkylating agent. The unsaturated derivative 8 reacts in high yields under mild conditions with dienes and 1,3-dipoles to give the corresponding cycloadducts. Elaboration of these compounds by acidic deprotection to substituted pyroglutaminols, and oxidation to the corresponding pyroglutamates, can be readily achieved.