Pericyclic organometallic reactions. Cycloaddition reactions of (η4-cycloheptatriene)Ru(CO)3. Crystal structure of tricarbonyl[(2,3,4,9-η)-bicyclo[4.2.1]non-2-ene-4,9-diyl-7,7,8,8-tetracarbonitrile]ruthenium
作者:Zeev Goldschmidt、Elisheva Genizi、Hugo E. Gottlieb、Dafna Hezroni-Langermann、Heinz Berke、H.William Bosch、Josef Takats
DOI:10.1016/0022-328x(91)86468-6
日期:1991.2
(eta-4-Cycloheptatriene)Ru(CO)3 reacts readily with tetracyanoethylene (TCNE), 4-phenyltriazoline-3,5-dione (PTAD) and (carbomethoxy)maleic anhydride (CMA) to give stable 3 + 2 sigma,pi-allylic adducts. The 3 + 2 adduct with TCNE equilibrates via a [4,4]-sigmahaptotropic rearrangement with the less stable 6 + 2 adduct, which decomposes under the reaction conditions to the demetallated 6 + 2 adduct. It is concluded that sigma,pi-allylic adducts are in general more stable than their isomeric eta-4-pi counter-parts. The strucuture of the 3 + 2 TCNE adduct was determined by a single-crystal X-ray diffraction study.
EDELMANN, FRANK;KIEL, GONG-YU;TAKATS, JOSEF;VASUDEVAMURTHY, ACHUTHA;YEUNG+, J. CHEM. SOC. CHEM. COMMUN.,(1988) N 4, 296-297