发现在甲基锂试剂存在下,几种高度模块化的手性氨基二醇三齿配体可有效用于芳族醛的不对称烷基化反应,在相对温和的条件下可提供高达96%的ee值和高达94%的收率。对这些配体的催化活性的研究表明,配体的对映选择性与取代的N-烷基和亲核的Li-烷基的空间特性有关。将Ti(O - Pr)4添加到配体3c中,1 H NMR光谱显示六配位的Ti过渡态络合物,溶液中仅生成一个Ti金属中心。
发现在甲基锂试剂存在下,几种高度模块化的手性氨基二醇三齿配体可有效用于芳族醛的不对称烷基化反应,在相对温和的条件下可提供高达96%的ee值和高达94%的收率。对这些配体的催化活性的研究表明,配体的对映选择性与取代的N-烷基和亲核的Li-烷基的空间特性有关。将Ti(O - Pr)4添加到配体3c中,1 H NMR光谱显示六配位的Ti过渡态络合物,溶液中仅生成一个Ti金属中心。
Trityl-Containing Alcohols—An Efficient Chirality Transmission Process from Inductor to the Stereodynamic Propeller and their Solid-State Structural Diversity
form aggregates stabilized by OH•••O hydrogen bonds. However, the presence of two trityl groups precludes formation of OH•••O hydrogen bonding. Additionally, the trityl group seems to be responsible for the formation of the solid solutions by e.g., racemates of trans- and cis-2-tritylcyclohexanol. Therefore, the trityl group acts as a supramolecular protective group, which in turn can be used in the
The synthesis of chiral amino diol tridentate ligands and their enantioselective induction during the addition of diethylzinc to aldehydes
作者:An-lin Zhang、Li-wen Yang、Nian-fa Yang、Yan-ling Liu
DOI:10.1016/j.tetasy.2013.11.007
日期:2014.2
A series of C2-symmetric chiral amino diol tridentate ligands 3a–g were prepared fromachiral bulky organolithiums, achiral bulky primary amines, and optically active epichlorohydrin (ECH). The prepared C2-symmetric chiral amino diol tridentate ligands were capable of inducing enantioselectivity in the model reaction of aromatic and aliphatic aldehydes with diethylzinc with an ee of up to 96%. The
Investigation of catalytic activity and catalytic mechanism of chiral amino diol tridentate ligands in the asymmetric addition of aldehydes in the present of methyllithium reagent
作者:An-Lin Zhang、Li-Wen Yang、Nian-Fa Yang、Da-Cai Liu
DOI:10.1016/j.jorganchem.2014.06.012
日期:2014.10
Several highly modular chiral amino diol tridentate ligands were found to be effective for the asymmetric alkylation reaction of aromatic aldehydes in the presence of methyllithium reagent, providing up to 96% ee values and up to 94% yields under relatively mild conditions. The investigation of the catalytic activity of these ligands shows a correlation of enantioselectivities of ligands with steric properties
发现在甲基锂试剂存在下,几种高度模块化的手性氨基二醇三齿配体可有效用于芳族醛的不对称烷基化反应,在相对温和的条件下可提供高达96%的ee值和高达94%的收率。对这些配体的催化活性的研究表明,配体的对映选择性与取代的N-烷基和亲核的Li-烷基的空间特性有关。将Ti(O - Pr)4添加到配体3c中,1 H NMR光谱显示六配位的Ti过渡态络合物,溶液中仅生成一个Ti金属中心。