Nickel-catalyzed regio- and stereoselective homo 1,4-dialkenylation of conjugated dienes
作者:Der-Ching Jou、Tsung-Yu Hsiao、Ming-Yuan Wu、Kwang-Cheng Kong、Chien-Hong Cheng
DOI:10.1016/s0040-4020(97)10205-8
日期:1998.2
and cyclic dienes react with β-iodoenones (RI: 3-Iodo-2-cyclohexen-1-one, 5,5-dimethyl-3-iodo-2-cyclohexen-1-one and 3-iodo-2-cyclopenten-1-one) in the presence of Zn and catalytic amount of NiBr2 to afford the corresponding homo 1,4-addition products in good yields. For 2,3-dimethyl-1,3-butadiene, only the products RCH2C(CH3)=C(CH3)CH2R with Z geometry were observed. For cyclic dienes, the products
2,3-二甲基-1,3-丁二烯和环状二烯与β-碘烯酮反应(RI:3-碘-2-环己烯-1-酮,5,5-二甲基-3-碘-2-环己烯-1- 1和3-碘-2-环戊烯-1-酮)在Zn的存在下和催化量的NiBr 2的存在,以良好的产率提供相应的均一的1,4-加成产物。为2,3-二甲基-1,3-丁二烯,只有产品RCH 2 C(CH 3)= C(CH 3)CH 2 R 2与几何三维观察。对于环状二烯,观察到的产物是其中两个烯基取代基R彼此顺式。