C-H bond functionalization via hydride transfer: Lewis acid catalyzed alkylation reactions by direct intramolecular coupling of sp3 C-H bonds and reactive alkenyl oxocarbenium intermediates.

ABSTRACT: C-H bond functionalization enables strategically new approaches to the synthesis of complex organic molecules including biologically active compounds, research probes and functional organic materials. To address the shortcomings of transition metal catalyzed processes, we have developed a new approach to direct coupling of sp(3) C-H bonds and alkenes based on Lewis acid-promoted hydride transfer. Activation of alpha,beta-unsaturated aldehydes and ketones with Lewis acid triggers intramolecular hydride transfer, leading to a zwitterionic intermediate, which in turn undergoes ionic cyclization to afford the cyclic alkylation product. The scope of this method is expanded by the generation of alkenyl-oxocarbenium species as highly activated alkene intermediates capable of abstracting a hydride

SUBMITTER: McQuaid KM 

PROVIDER: S-EPMC2954885 | biostudies-literature | 2009 Jan

REPOSITORIES: biostudies-literature