The enantioselective Pd-catalyzed allylation reaction of fluorinated allyl enol carbonates is presented; a key feature of this transformation is the important effect of the ligand-to-palladium ratio on the enantioselectivity of the α-fluoroketones, since using a ligand excess (L/Pd ratio = 1.25 : 1) led to moderate results (30–76% ee), while using a L/Pd ratio <1 : 1.67 (to as low as 1 : 4) allowed the desired products to be obtained with high enantiopurity (up to 94% ee).
介绍了 Pd 催化的
氟化烯丙基烯醇
碳酸酯的对映体选择性烯丙基化反应;这一转化的一个关键特征是
配体与
钯的比率对 α-
氟酮的对映体选择性的重要影响,因为使用
配体过量(L/Pd 比率 = 1.25 : 1)会导致中等结果(30-76% ee),而使用 L/Pd 比 <1 : 1.67(低至 1 : 4)则可获得高对映体纯度(高达 94% ee)的所需产物。