Hydrogen Bonding-Assisted Enhancement of the Reaction Rate and Selectivity in the Kinetic Resolution of <i>d,l</i>
-1,2-Diols with Chiral Nucleophilic Catalysts
作者:Kazuki Fujii、Koichi Mitsudo、Hiroki Mandai、Seiji Suga
DOI:10.1002/adsc.201700057
日期:2017.8.17
An extremely efficient acylative kinetic resolution of d,l‐1,2‐diols in the presence of only 0.5 mol% of binaphthyl‐based chiral N,N‐4‐dimethylaminopyridine was developed (selectivity factor of up to 180). Several key experiments revealed that hydrogen bonding between the tert‐alcohol unit(s) of the catalyst and the 1,2‐diol unit of the substrate is critical for accelerating the rate of monoacylation
在仅0.5 mol%的联萘基手性N,N -4-二甲基氨基吡啶存在下,开发了一种极有效的d,l - 1,2-二醇的酰基动力学拆分方法(选择性因子高达180)。几个关键实验表明,催化剂的叔醇单元与底物的1,2-二醇单元之间的氢键键合对于加快单酰化速率和实现高对映选择性至关重要。该催化体系可广泛应用于涉及外消旋无环和环状1,2-二醇且具有高选择性因子的底物。d,l-氢安息香和反式的动力学拆分数克级(10 g)的1,2-环己二醇也具有较高的选择性并在中等反应条件下进行:(i)催化剂负载量极低(0.1 mol%); (ii)容易达到的低反应温度(0°C);(iii)高底物浓度(1.0 M);(iv)反应时间短(30分钟)。