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Synthesis of N-(2,3,4,5,6-Pentafluorobenzyloxy)--lactams by Rhodium-Catalyzed Cyclization of Diazo Amides. -A series of diazo amides bearing the -Fbo protecting group is successfully cyclized to -lactam structures with different yields and stereoselectivities. Product (IV) represents a precursor of the important GABA analogue gabapentin hydrochloride (V). Investigation of an asymmetric version leads to a promising result only in the case of (XIII). Educt (XVII) does not follow the expected cyclization pathway but undergoes Buechner reaction to the cycloheptatriene (XVIII). -(BUDNY, M.; NOWAK, M.; WOJTCZAK, A.; WOLAN*, A.; Eur. J. Org. Chem. 2014, 29, 6361-6365, http://dx.doi.org/10.1002/ejoc.201402571 ; Fac. Chem., Nicolaus Copernicus Univ., PL-87-100 Torun, Pol.; Eng.) -Lehmann 13-169

Rhodium‐catalyzed cyclization of N‐(2,3,4,5,6‐pentafluoro‐benzyloxy) diazo amides leading to the corresponding γ‐lactams is described. The cyclization is based on the intramolecular catalytic insertion into the C–H bond. Fourteen lactams were obtained with up to 91 % yield and 88 % ee. Gabapentin hydrochloride, a GABA analog, was also synthesized by this method, which shows that deprotection of the 2,3,4,5,6‐pentafluorobenzyloxy group is possible.