Palladium-Catalyzed Asymmetric Diene Cyclization/Hydrosilylation Employing Functionalized Silanes and Disiloxanes
作者:Tao Pei、Ross A. Widenhoefer
DOI:10.1021/jo015724n
日期:2001.11.1
diallylmalonate (1) and other functionalized 1,6-dienes in the presence of a catalytic 1:1 mixture of (N-N)Pd(Me)Cl [N-N = (R)-(+)-4-isopropyl-2-(2-pyridinyl)-2-oxazoline] [(R)-2] and NaBAr(4) [Ar = 3,5-C(6)H(3)(CF(3))(2)] to form the corresponding silylated cyclopentanes in good yield with high diastereoselectivity. The enantioselectivity of cyclization/hydrosilylation of 1 with disiloxanes and functionalized
HSiMe(2)CH(x)Ph(3-x)(x = 1或2)形式的五取代二硅氧烷和硅烷与二烯丙二酸二甲酯(1)和其他功能化的1,6-二烯在催化1存在下反应:1(NN)Pd(Me)Cl [NN =(R)-(+)-4-异丙基-2-(2-吡啶基)-2-恶唑啉] [(R)-2]和NaBAr(4 )[Ar = 3,5-C(6)H(3)(CF(3))(2)]以高收率和高非对映选择性形成相应的甲硅烷基化环戊烷。1在20摄氏度下与二硅氧烷和官能化硅烷的1的环化/氢化硅烷化的对映选择性按以下顺序增加:HSiMe(2)OSiMe(3)(75%ee)