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Divergent C-H Insertion-Cyclization Cascades of N-Allyl Ynamides.

ABSTRACT: Gold carbene reactivity patterns were accessed by ynamide insertion into a C(sp(3) )H bond. A substantial increase in molecular complexity occurred through the cascade polycyclization of N-allyl ynamides to form fused nitrogen-heterocycle scaffolds. Exquisite selectivity was observed despite several competing pathways in an efficient gold-catalyzed synthesis of densely functionalized C(sp(3) )-rich polycycles and a copper-catalyzed synthesis of fused pyridine derivatives. The respective gold-keteniminium and ketenimine activation pathways have been explored through a structure-reactivity study, and isotopic labeling identified turnover-limiting CH bond-cleavage in both processes.

SUBMITTER: Adcock HV

PROVIDER: S-EPMC4832826 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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Divergent C-H Insertion-Cyclization Cascades of N-Allyl Ynamides.

Adcock Holly V HV Chatzopoulou Elli E Davies Paul W PW

Angewandte Chemie (International ed. in English) 20151030 51

Gold carbene reactivity patterns were accessed by ynamide insertion into a C(sp(3) )H bond. A substantial increase in molecular complexity occurred through the cascade polycyclization of N-allyl ynamides to form fused nitrogen-heterocycle scaffolds. Exquisite selectivity was observed despite several competing pathways in an efficient gold-catalyzed synthesis of densely functionalized C(sp(3) )-rich polycycles and a copper-catalyzed synthesis of fused pyridine derivatives. The respective gold-ke ...[more]

PMID: 26515958

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