Chiral chelating agents and chiral catalysts, which are formed from the chiral chelating agents and metal, are described. One chiral chelating agent has a general formula (1) as illustrated below:
1
wherein R represents H, methyl, ethyl, a primary, secondary or tertiary straight, branched or cyclic alkyl group having 3-7 carbon atoms, a heterocyclic or aromatic group, an aromatic group substituted at the 2-, 3- or 4-position, an aromatic-like group, or a naphthyl or naphthyl-derived group, and n is an integer between 0 and 4.
A Bifunctional β-Isocupreidine Derivative as Catalyst for the Enantioselective Morita-Baylis-Hillman Reaction and a Mechanistic Rationale for Enantioselectivity
作者:Gianluca Martelli、Mario Orena、Samuele Rinaldi
DOI:10.1002/ejoc.201200405
日期:2012.8
Starting fromβ-isocupreidine (β-ICD), a series of difunctional catalysts were synthesized to ascertain their usefulness in the asymmetric Morita–Baylis–Hillman (MBH) reaction. The trichloroacetylcarbamate derivative was found to give the (R)-MBH adducts in excellent optical purities (90–99 % ee) and moderate to good yields (43–83 %), in some cases, better than β-ICD. A number of acrylates were also
Study of the stereoselectivity of the nucleophilic epoxidation of 3-hydroxy-2-methylene esters
作者:Antonio Latorre、José A. Sáez、Santiago Rodríguez、Florenci V. González
DOI:10.1016/j.tet.2013.11.014
日期:2014.1
The diastereoselectivity of the nucleophilic epoxidation of 3-hydroxy-2-methylene esters has been studied. The 3-hydroxy-2-methylene esters were obtained through a Morita-Baylis-Hillman reaction. The resulting epoxyesters were treated with thiophenol for transformation into 2,3-dihydroxy-2-((phenylthio)methyl), which upon treatment with triphosgene afforded the corresponding cyclic carbonates. (C) 2013 Elsevier Ltd. All rights reserved.
Adam, Waldemar; Hoch, Ute; Saha-Moeller, Chantu R., Angewandte Chemie, 1993, vol. 105, # 12, p. 1800 - 1801
作者:Adam, Waldemar、Hoch, Ute、Saha-Moeller, Chantu R.、Schreier, Peter