The stereoselective synthesis of α-substituted β-amino secondary alcohols based on the proline-mediated, asymmetric, three-component Mannich reaction and its application to the formal total synthesis of nikkomycins B and Bx
作者:Yujiro Hayashi、Tatsuya Urushima、Makoto Shin、Mitsuru Shoji
DOI:10.1016/j.tet.2005.09.013
日期:2005.11
general method for the asymmetric synthesis of α-substituted β-amino secondary alcohols is described, which comprises the four-reaction sequence (1) the proline-mediated, asymmetric, three-component Mannich reaction of two different aldehydes, (2) nucleophilic carbon addition to aldehyde, (3) oxidation of the resulting alcohol to the corresponding ketone, and (4) diastereoselective reduction with LiAlH(O-t-Bu)3
描述了一种不对称合成α-取代的β-氨基仲醇的一般方法,该方法包括四个反应序列(1)脯氨酸介导的两种不同醛的不对称三组分曼尼希反应,(2)亲核碳除醛外,(3)将生成的醇氧化为相应的酮,以及(4)用LiAlH(O- t- Bu)3或儿茶酚硼烷进行非对映选择性还原。前一种还原剂可提供1,2-顺式异构体,而后者可选择性地立体异构地提供1,2-抗异构体。本方法已成功地应用于尼克霉素B和B X的N-末端氨基酸部分的有效不对称合成。