Simple and efficient Grignard procedures are reported for the syntheses of B-allenyl-10-(phenyl)-9-borabicyclo[3.3.2]decane (1) and its B-(gamma-trimethylsilylpropargyl) counterpart (2) in both enantiomeric forms. Both add selectively to ketones, providing propargyl- and alpha-silylallenyl 3-degree-carbinols, respectively (i.e., 6 (61-93% ee) and 9 (64-98% ee)). The air-stable boron byproduct is efficiently
据报道,简单有效的Grignard方法可合成两种对映体形式的B-烯基-10-(苯基)-9-环
硼[3.3.2]
癸烷(1)及其对应的B-(γ-三甲基甲
硅烷基炔丙基)(2)。 。两者都选择性地添加到酮中,分别提供炔丙基和α-甲
硅烷基烯丙基3-度羰基化合物(即6(61-93%ee)和9(64-98%ee))。空气稳定的
硼副产物可有效回收并循环回1或2。9的
臭氧分解和
溴化分别提供非外消旋的α-羟基酸和γ-
溴丙炔基
甲醇。