Ruthenium-catalyzed stereoselective intramolecular carbenoid C-H insertion for beta- and gamma-lactam formations by decomposition of alpha-diazoacetamides.
[reaction: see text] An operationally simple catalytic system based on [RuCl(2)(p-cymene)(2)] was developed for stereoselective cyclization of alpha-diazoacetamides by intramolecular carbenoid C-H insertion, and beta-lactams were produced in excellent yields and >99% cis-stereoselectivity. The Ru-catalyzed reactions can be performed without the need for slow addition of diazo compounds and inert atmosphere. With alpha-diazoanilides as substrate, the carbenoid insertion was directed selectively to aromatic C-H bond leading to gamma-lactam formation (>95% yield).
Choi
Matthew Kwok-Wai
MK
Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong.
Yu
Wing-Yiu
WY
Che
Chi-Ming
CM
D002384:Catalysis; D003500:Cyclization; D003979:Diazonium Compounds / Q000737:chemistry*; D007769:Lactams / Q000138:chemical synthesis*; D015394:Molecular Structure; D012428:Ruthenium / Q000737:chemistry*; D013237:Stereoisomerism
D003979:Diazonium Compounds; D007769:Lactams; C011752:diazoacetamide; D012428:Ruthenium