Synthesis of Chiral<i>N</i>-Sulfonyl and<i>N</i>-Phosphinoyl α-Halo Aldimine Precursors
作者:Gretchen R. Stanton、Mehmet Göllü、Rebecca M. Platoff、Corinne E. Rich、Patrick J. Carroll、Patrick J. Walsh
DOI:10.1002/adsc.201200864
日期:2013.3.11
aldimines have emerged as an important class of synthetic intermediates. The stability and reactivity of α‐halo aldimines can vary greatly depending on the nitrogen protecting group. A general synthesis of stable, chiral α‐halo‐N‐sulfonyl and N‐phosphinoyl aldimine precursors is presented (42–96% yield). The corresponding α‐halo aldimines can be isolated upon treatment with a mild base. Enantioenriched α‐chloro
Chelation-Controlled Addition of Organozincs to α-Chloro Aldimines
作者:Gretchen R. Stanton、Per-Ola Norrby、Patrick J. Carroll、Patrick J. Walsh
DOI:10.1021/ja306781z
日期:2012.10.24
report is C-X bonds reversing the diastereoselectivity throughcoordination to metals during C-C bond-forming reactions (chelationcontrol). Herein we describe chelationcontrol involving C-X bonds in highly diastereoselective additions of organozinc reagents to a variety of α-chloro aldimines. The unique ability of alkylzinc halide Lewisacids to coordinate to the Cl, N, and O of α-chloro sulfonyl
众所周知,α-手性 α-卤代羰基衍生物的亲核加成可通过非螯合途径生成 Cornforth-Evans 产物。在本报告之前前所未有的是 CX 键通过在 CC 键形成反应(螯合控制)期间与金属配位来逆转非对映选择性。在此,我们描述了在将有机锌试剂高度非对映选择性添加到各种 α-氯醛亚胺中时涉及 CX 键的螯合控制。计算研究支持烷基锌卤化物路易斯酸与 α-氯磺酰基亚胺底物的 Cl、N 和 O 配位的独特能力。