The rhodium-catalyzed 1,2-addition of chiral benzylic secondary alkylboronic esters with a coordinating carbonyl group to aldehydes was demonstrated with high levels of enantiospecificity. Pinacol boronic ester derivatives can be employed directly for the addition in the presence of KHF2 without the use of corresponding trifluoroborate salts where retention of the configuration was observed. Enantiomerically
铑与手性苄基仲烷基
硼酸酯的
铑催化1,2-加成反应后,对映体的对映体特异性很高。品那可
硼酸酯衍
生物可以在KHF 2存在下直接用于加成反应,而无需使用相应的三
氟硼酸盐,因为在这种情况下观察到了构型的保留。以良好的产率合成了对映体富集的β,γ-二芳基取代的
γ-丁内酯。