Asymmetric Allylboration of Ketones Catalyzed by Chiral Diols
作者:Sha Lou、Philip N. Moquist、Scott E. Schaus
DOI:10.1021/ja0651308
日期:2006.10.1
Chiral BINOL-derived diols catalyze the enantioselective asymmetricallylboration of ketones. The reaction requires 15 mol % of 3,3‘-Br2-BINOL as the catalyst and allyldiisopropoxyborane as the nucleophile. The reaction products are obtained in good yields (76−93%) and high enantiomeric ratios (95:5−99.5:0.5). High diastereoselectivities (dr ≥ 98:2) and enantioselectivities (er ≥ 98:2) are obtained
Cu‐Catalyzed Chemoselective Preparation of 2‐(Pinacolato)boron‐Substituted Allylcopper Complexes and their In Situ Site‐, Diastereo‐, and Enantioselective Additions to Aldehydes and Ketones
作者:Fanke Meng、Hwanjong Jang、Byunghyuck Jung、Amir H. Hoveyda
DOI:10.1002/anie.201301018
日期:2013.5.3
Sustainable, efficient, selective: A three‐component, single‐vessel Cu‐catalyzed method for chemo‐, diastereo‐, and enantioselective conversion of B2(pin)2, monosubstituted allenes, and aldehydes or ketones to 2‐B(pin)‐substituted homoallylic alkoxides is described. Subsequent functionalization delivers valuable products in up to >98:2 d.r. and 97:3 e.r. (see scheme).
可持续、高效、选择性:一种三组分、单容器铜催化方法,用于 B 2 (pin) 2、单取代丙二烯和醛或酮向 2-B(pin) 的化学、非对映和对映选择性转化描述了-取代的高烯丙基醇盐。随后的功能化可提供高达 >98:2 dr 和 97:3 er 的有价值的产品(参见方案)。
Catalytic Enantioselective Allylboration of Ketones
The first example of catalyticenantioselective allylboration and crotylboration of simple ketones is described. High enantioselectivity (up to 93% ee) was obtained using 3 mol % CuF-iPr-DuPHOS as a chiral catalyst and 4.5 mol % La(OiPr)3 as a cocatalyst. Mechanistic studies strongly suggested that the active nucleophile of the present reaction is an allylcopper, and that La(OiPr)3 facilitates the
Silver-Catalyzed Asymmetric Sakurai−Hosomi Allylation of Ketones
作者:Manabu Wadamoto、Hisashi Yamamoto
DOI:10.1021/ja0553351
日期:2005.10.1
allylation of simple ketones. A significaant improvement of the reactivity was observed by using THF as the solvent. The catalyst turnover was increased by addition of 1 equiv of MeOH. AgF and (R)-DIFLUORPHOS predominantly formed a 1:1 complex that provided high enantioselectivity. This catalyst system can be applied to various simple ketones, and corresponding tertiaryhomoallylicalcohols were obtained