New approaches to polysubstituted pyrroles and gamma-lactams based on nucleophilic addition of Ti(IV) enolates derived from alpha-diazo-beta-keto carbonyl compounds to N-tosylimines.
The Ti(IV) enolates derived from alpha-diazo-beta-keto esters or ketones efficiently add to TiCl4-activated N-tosylimines to give delta-N-tosylamino substituted alpha-diazo-beta-keto carbonyl compounds. The diazo decomposition of the addition products occurs under Rh2(OAc)4-catalyzed or photoinduced conditions to afford pyrrole or gamma-lactam derivatives, both in high yields.
Dong
Changqing
C
Beijing National Laboratory of Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China.
Deng
Guisheng
G
Wang
Jianbo
J