Ruthenium-assisted synthesis of gem-deuterated alkenes from monosubstituted propargyl alcohols and D2O
作者:Claudio Bianchini、Isaac de los Rios、Carlos Lopez、Maurizio Peruzzini、Antonio Romerosa
DOI:10.1016/s0022-328x(99)00324-1
日期:2000.1
The cyclohexenylvinylidene complex fac,cis-[(PNP)RuCl2C=CH(C=CHCH2CH2CH2CH2)}] (2) is synthesized by reaction of mer, trans-[(PNP)RuCl2(PPh3)] (1) with 1-ethynylcyclohexanol [PNP=CH3CH2CH2N(CH2CH2PPh2)(2)]. Complex 2 reacts with water yielding fac,cis-[(PNP)RuCl2(CO)] and methylenecyclohexane. The regioselective incorporation of deuterium from D2O into the methylene group of methylenecyclohexane is consistent with the intermediacy of an eta(1)-allyl ruthenium complex along the metal-assisted hydrolysis of the vinylidene C-C bond. The hydrolysis of the alkenylvinylidenes fac,cis-[(PNP)RuCl2C=CHCR=CH2}] (R = Me, Ph) proceeds similarly but the regioselectivity of deuterium incorporation depends on the temperature due to eta(1) double left right arrow eta(3) allyl interconversion. (C) 2000 Elsevier Science S.A. All rights reserved.