R. Annunziata et al., The effect of Lewis acids on the pinacol homocoupling reaction of aldehydes promoted by samarium diiodide, EUR J ORG C, (12), 1999, pp. 3369-3374
The effect of various Lewis acids on the samarium diiodide promoted pinacol
homocoupling of aldehydes was investigated. The reaction of benzaldehyde p
roceeded with fair to good 1,2-anti-stereoselectivity, while in the case of
other aromatic and aliphatic aldehydes syn-stereoselectivity was generally
observed. Chiral alpha-alkylaldehydes allowed for an almost complete stere
ocontrol favoring syn-1,2-diols.