Oxidative Addition of Secondary C–X Bonds to Palladium(0): A Beneficial Anomeric Acceleration

The oxidative addition of secondary electrophiles to Pd(0) is significantly accelerated by anomeric effects. In contrast to cyclohexyl bromide, acetobromo-α-d-glucose undergoes invertive oxidative addition to tris(triethylphosphine)palladium(0) to generate a stable, isolable organometallic complex, Pd(PEt3)2(Br)(AcO-β-glucose), which has been fully characterized but is prone to β-acetoxy elimination.

异头效应（anomeric effects）可显著加速仲亲电试剂与零价钯（Pd(0)）的氧化加成反应。与溴代环己烷（cyclohexyl bromide）不同，乙酰溴-α-D-葡萄糖（acetobromo-α-D-glucose）可与三(三乙基膦)合钯(0)（tris(triethylphosphine)palladium(0)）发生构型翻转型氧化加成，生成稳定且可分离的有机金属配合物Pd(PEt3)2(Br)(AcO-β-glucose)；该配合物已得到充分表征，但易发生β-乙酰氧基消除反应。