Asymmetric intramolecular alkylation of indoles with unactivated olefins

ORGN 272

Xiaoqing Han, xh5@duke.edu and Ross A. Widenhoefer, rwidenho@duke.edu. Department of Chemistry, Duke University, P. M. Gross Chemical Laboratory, Durham, NC 27708
Enantiomerically pure platinum bis(phosphine) catalysts proved effective for the asymmetric alkylation of alkenyl indoles. For example, reaction of 2-(2,2-dicarbomethoxy-4-pentenyl)-1-methyl-1H-indole with a catalytic 1:1 mixture of (S)¨C3,5-t-Bu-4-MeO-MeOBIPHEPPtCl2 (1) and AgOTf at 60 oC for 20 h led to the isolation of 2,2-dicarbomethoxy-4,9-dimethyl-1,3,4,9-tetrahydrocarbazole in 93 % yield with 90 % ee. This protocol was applied to a variety of alkenyl indoles to give corresponding tetrahydrocarbazoles with good to excellent ee.

 

Asymmetric Reactions and Syntheses
8:00 AM-12:00 PM, Monday, 14 March 2005 Convention Center -- Room 11A, Oral

Division of Organic Chemistry

The 229th ACS National Meeting, in San Diego, CA, March 13-17, 2005