开发和优化了两种不同的方案,以满足在确定仲醇的绝对构型时对(1)高灵敏度或(2)方便利用的需求。第一种协议使用竞争对映选择性转化(CEC)方法来确定纳米分子规模的构型。使用50μL微型注射器作为反应容器,以145 nmol的底物进行反应,并通过薄层色谱法对快速反应进行定性确定绝对构型。该方案使以前的CEC方法研究所需的材料减少了50倍。用苄基和β-芳基体系评估了该方法。第二种方案经过优化,可满足从业药物化学家的需求。开发了一种一次性使用的CEC套件,1 H NMR光谱法和薄层色谱法。为微注射器方案开发的CEC反应条件和一次性试剂盒均显示与底物中拟一级动力学一致的数据。因此,对于底物的灵敏度的下限仅受有效检测醇底物与酯产物之间的反应转化的能力的限制。
Enantioselective acyl transfer catalysts and their use in kinetic resolution of alcohols and desymmetrization of meso-diols
申请人:Birman Vladimir
公开号:US20050256150A1
公开(公告)日:2005-11-17
Novel enantioselective acylation catalysts comprising chiral derivatives of DHIP and DHIQ, having the following representative general structures are disclosed:
These new compounds are useful for resolving racemates or further enhancing the enantiomeric excess of an enantiomerically enriched composition and for desymmetrizing meso compounds.
2,3-Dihydroimidazo[1,2-a]pyridines: A New Class of Enantioselective Acyl Transfer Catalysts and Their Use in Kinetic Resolution of Alcohols
作者:Vladimir B. Birman、Eric W. Uffman、Hui Jiang、Ximin Li、Corey J. Kilbane
DOI:10.1021/ja0491477
日期:2004.10.1
unexplored 2,3-dihydroimidazo[1,2-a]pyridine (DHIP) has been shown to be a competent acyl transfer catalyst. Its chiral 2-phenyl derivatives obtainable in two steps from commercially available starting materials have proved to be effective acylation catalysts, giving high levels of enantioselectivity (s = 20-85) in kineticresolution of secondary benzylic alcohols. A transition state model explaining
A Highly Selective Ferrocene-Based Planar Chiral PIP (Fc-PIP) Acyl Transfer Catalyst for the Kinetic Resolution of Alcohols
作者:Bin Hu、Meng Meng、Zheng Wang、Wenting Du、John S. Fossey、Xinquan Hu、Wei-Ping Deng
DOI:10.1021/ja108238a
日期:2010.12.1
Novel planar chiral ferrocene nucleophilic catalysts (Fc-PIP) containing both central and planar chiral elements were designed and synthesized for catalytic enantioselective acyltransfer of secondary alcohols. A remarkably efficient catalyst with high selectivity factors (up to S = 1892) was identified. Comparing the combination of central and planar chirality revealed a strong requirement for the
设计并合成了含有中心和平面手性元素的新型平面手性二茂铁亲核催化剂(Fc-PIP),用于仲醇的对映选择性酰基转移。鉴定出具有高选择性因子(高达 S = 1892)的非常有效的催化剂。比较中心手性和平面手性的组合揭示了对“匹配”手性元素的强烈要求,表明咪唑环的立体中心应与二茂铁片段位于同一面上;否则,催化剂完全失活。提出了一种完全堆叠的过渡态,它解释了仲醇动力学拆分的高选择性。尤其,