First preparation of allyl vanadium reagents in a mixed solvent of THF and HMPA (HMPA = hexamethylphosphoric triamide) and their application to allylation of carbonyl compounds
作者:Yasutaka Kataoka、Isamu Makihira、Kazuhide Tani
DOI:10.1016/0040-4039(96)01579-1
日期:1996.9
Allylation of carbonylcompounds with allyl bromide mediated by a vanadium(II) complex in a mixedsolvent of THF and HMPA (HMPA = hexamethylphosphorictriamide) has been accomplished. Coordination of HMPA to a vanadium metal is essential for the stabilization of the allylvanadium species.
A novel procedure for the reduction and pinacol coupling of aromatic aldehydes and ketones mediated by titanocene(III)/Zn in water is described. The titanocene-catalyzed version in sea water proved to be especially convenient for the reduction of aryl ketones. Mechanistically, the reaction presumably proceeds via free-radical chemistry.