A new type of catalytic tandem 1,4-addition-aldol reaction which proceeds through an (oxa-pi-allyl)rhodium intermediate

Kazuhiro Yoshida; Masamichi Ogasawara; Tamio Hayashi

doi:10.1021/ja0271025

A new type of catalytic tandem 1,4-addition-aldol reaction which proceeds through an (oxa-pi-allyl)rhodium intermediate

J Am Chem Soc. 2002 Sep 18;124(37):10984-5. doi: 10.1021/ja0271025.

Authors

Kazuhiro Yoshida¹, Masamichi Ogasawara, Tamio Hayashi

Affiliation

¹ Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan.

PMID: 12224938
DOI: 10.1021/ja0271025

Abstract

The reaction of 9-aryl-9-borabicyclo[3.3.1]nonanes (B-Ar-9BBN) with alpha,beta-unsaturated ketones and aldehydes in the presence of 3 mol % [Rh(OMe)(cod)](2) in toluene at 20 degrees C for 2 h gave high yields of the tandem 1,4-addition-aldol reaction products with high syn selectivity. The reaction proceeds through the catalytic cycle consisting of 1,4-addition of an organorhodium species to an alpha,beta-unsaturated ketone and the aldol addition of the resulting (oxa-pi-allyl)rhodium intermediate to an aldehyde.