The dicationic diruthenium complex 1c (Ru-III-Ru-III) catalytically promotes the dimerization of alpha-methylstyrenes into the corresponding acyclic dimers, while the use of the mixed-valence diruthenium complex (Ru-III-Ru-IV) generated from 1c and cinnamyl chloride as an active catalyst affords the corresponding indanes via cyclization of the acyclic dimers. The selectivity of the catalytic dimerization of alpha-methylstyrenes depends on the nature of electrophilicity due to valence electrons in the diruthenium cores between Ru-III-Ru-III and Ru-III-Ru-IV.
Glycerol as An Efficient Promoting Medium for Organic Reactions
作者:Yanlong Gu、Joël Barrault、François Jérôme
DOI:10.1002/adsc.200800328
日期:2008.9.5
beneficial effect of water on reaction rate is decreased with an increase of the reactant′s hydrophobicity, we report here that the use of glycerol as solvent was able to considerably accelerate the reaction rate of an organicreaction even starting from more hydrophobic substrates than those usually used on water. Moreover, the possibility of directly using crude glycerol generated by the biodiesel industry