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,
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
Bi-aryl rotation in phenyl-dihydroimidazoquinoline catalysts for kinetic resolution of arylalkyl carbinols
作者:Zheng Wang、Jinjin Ye、Rui Wu、Yang-Zi Liu、John S. Fossey、Jiagao Cheng、Wei-Ping Deng
DOI:10.1039/c3cy00904a
日期:——
Chiral nucleophilic catalysts, 6-aryl-phenyl-dihydroimidazoquinolines (PIQs), were designed, synthesised and applied to the kineticresolution of arylalkyl carbinols with very high selectivity (S) factors (up to 530). Density functional theory calculations indicate that multiple noncovalent interactions play a key role in chiralrecognition between 6-aryl-PIQ catalysts and chiral secondary alcohol
2,2-Disubstituted Propionic Anhydrides: Effective Coupling Reagents for the Kinetic Resolution of Secondary Benzylic Alcohols Using BTM
作者:Isamu Shiina、Kenya Nakata、Masuhiro Sugimoto、Yu-suke Onda、Takashi Iizumi、Keisuke Ono
DOI:10.3987/com-08-s(f)75
日期:——
variety of opticallyactive benzylic alcohols possessing aliphatic substituents at the C-1 position are produced by the kinetic resolution of racemic secondary alcohols using free carboxylicacids with 2,2-disubstituted propionic anhydrides and (+)-benzotetramisole (BTM). Evaluation of the efficiency of this asymmetric esterification using several anhydrides derived from aliphatic carboxylicacids were carried
The first asymmetric esterification of free carboxylic acids with racemic alcohols using benzoic anhydrides and tetramisole derivatives: an application to the kinetic resolution of secondary benzylic alcohols
作者:Isamu Shiina、Kenya Nakata
DOI:10.1016/j.tetlet.2007.09.135
日期:2007.11
non-substituted benzoic anhydride is used as a coupling reagent, the resulting opticallyactivealcohols are obtained with high selectivities. This protocol directly produces chiral carboxylic esters from free carboxylic acids and racemic secondary alcohols by utilizing the trans-acylation process to generate mixed anhydrides from acid components and benzoic anhydride derivatives under the influence of chiral