Reductive coupling of carbonyl compounds using lanthanum metal

We found that lanthanum metal was an excellent agent for the reduction of c arbonyl compounds in the presence of a catalytic amount of iodine. When car bonyl compounds were treated with lanthanum metal in the presence of a cata lytic amount of iodine, the reductive coupling of the carbonyl compounds pr oceeded efficiently to afford the corresponding vic-diols in moderate to go od yields. (C) 2000 John Wiley & Sons, Inc.