Site-Selective C8-Alkylation of Quinolines with Cyclopropanols: Merging C–H/C–C Bond Activation

Abstract

The site-selective C8-alkylation of quinolines has been accomplished using cyclopropyl alcohols as the alkylating agents and N-oxide as a weak chelating group in the presence of Co(III) catalysis via merging C−H/C−C bond activation. The use of cyclopropanol as the alkyl source, Co catalysis, substrate scope, HRMS analysis of the reaction intermediate, and late-stage mutation of drug molecules/ natural products are the important practical features.

Palladium-Catalyzed Regioselective Insertion of Carbenes into γ-C(sp3)–H Bonds of Aliphatic Amines

“…15 The Krapcho decarboxylation of 3a was successfully executed to yield the monoester 6 in a 72% yield (Scheme 4d). 16 In summary, we have unveiled a regioselective insertion of carbenes into distal γ-C(sp 3 )−H bonds of aliphatic amines. The crucial step involves palladium-catalyzed, picolinamideassisted γ-C(sp 3 )−H activation.…”

N‐Pyridylureas as Masked Isocyanates Fort the Late‐Stage Diversification of Pyridine‐N‐Oxides

“…However, in the last decade, methods of late-stage modification/diversification have become more significant in the organic synthesis, since this approach provides rapid identification and optimization of hit and lead compounds, as well as open access to potential intermediates and metabolites. [60][61][62] This approach has also begun to be considered for the modification of the side chains of substituted azine-N-oxides, but so far not enough published work has been done (for some recent examples see Refs [63][64][65][66][67][68][69] ). Thus, the emergence of a new procedure for the functionalization of N-oxides that does not affect the NÀ O bond is of great interest.…”