The directed ortho-lithiation of aryl tetramethylphosphorodiamidates.
作者:Mitsuaki WATANABE、Mutsuhiro DATE、Kenji KAWANISHI、Takako HORI、Sunao FURUKAWA
DOI:10.1248/cpb.38.2637
日期:——
Aryl tetramethylphosphorodiamidates were effectively ortho-lithiated with sec-BuLi in tetrahydrofuran at -105°C.The resulting lithiated species were trapped with a variety of electrophiles at -105°C to provide ortho-substituted phosphorodiamidates. When the lithiation was carried out at -78°C, O→C migration of the bis(dimethylamino)phosphoryl group took place rapidly and 2-hydroxyarylphosphonic tetramethyldiamides were produced regioselectively. The ortho-directing ability of the phosphorodiamidates was investigated by intermolecular competition experiments with other directed metalation groups.
芳基四甲基膦双胺盐在四氢呋喃中,以-105°C温度下通过第二丁基锂有效实现邻位锂化。所得锂化物种与各种亲电试剂在-105°C温度下反应,生成邻位取代的膦双胺盐。当锂化反应在-78°C进行时,双(二甲基氨基)膦基团迅速发生O→C迁移,选择性地生成2-羟基芳基膦酸四甲基双胺盐。通过与其他导向金属化基团的分子间竞争实验研究了膦双胺盐的邻位导向能力。