Synthesis of fluorinated materials catalyzed by proline or antibody 38C2 in ionic liquid
摘要:
The utility of reusable ionic liquid-proline (or aldolase antibody 38C2) reaction system, proceeding the aldol reactions, is described. Further. obtained alpha-chloro-beta-hydroxy compounds were transformed to the optically active alpha,beta-epoxy carbonyl compounds. The aldolase antibody 3SC2-ionic liquid system was able to reuse in Michael additions and the reaction of fluoromethylated imines. (C) 2003 Elsevier Science B.V. All rights reserved.
Compounds useful as plasticizers and the synthesis thereof are disclosed. In general, the invention includes mixed alkyl/aryl asymmetric cyclic diesters where the aryl and alkyl ester moieties are attached to a cyclic structure at vicinal carbons. The invention also includes synthetic processes of making such compounds. Blends of these asymmetric cyclic diesters with other plasticizers are demonstrated to be of use in plasticizing polymers.
for the asymmetric aldol reaction of chloroacetone. The stereoselective synthesis of vic-halohydrins was accomplished with excellent regioselectivity (>99%) to generate α-chloro-β-hydroxy ketones with high syn selectivity (syn/anti = 16:1) and enantioselectivity (up to 95% ee). aldol reaction - amino acids - asymmetric synthesis - chloroacetone - organocatalysis
升-叔-亮氨酸被认为是为氯丙酮的不对称醛醇缩合反应的有效有机催化剂。vic-卤代醇的立体选择性合成具有出色的区域选择性(> 99%),可生成具有高syn选择性(syn / anti = 16:1)和对映选择性(高达95%ee)的α-氯-β-羟基酮。 Aldol反应-氨基酸-不对称合成-氯丙酮-有机催化
Stereoselective synthesis of vic-halohydrins and an unusual Knoevenagel product from an organocatalyzed aldol reaction: A non-enamine mode
aldol reaction between chloroacetone and aldehyde was studied using a synthesized chiral organocatalyst and triethylamine. The reaction gave α-chloro-β-hydroxy ketones in excellent yield with high anti selectivity and enantioselectivity. The chiral organocatalyst was also used in the Knoevenagel reaction, which gave α-cyano-β-hydroxy ketones at a low temperature and the usual Knoevenagel product at a
Basic character of rare earth metal alkoxides. Utilization in catalytic carbon-carbon bond-forming reactions and catalytic asymmetric nitroaldol reactions
in organic synthesis. However, all reactions examined were performed with stoichiometric quantities of the reagent. The authors envisioned that rare earth metal alkoxides would be stronger bases than group 4 metal alkoxides due to the lower ionization potential (ca. 5.4-6.4 eV) and the lower electronegativity (1.1-1.3) of rare earth elements; thus, the catalytic use of rare earth metal alkoxides in
[EN] RACEMOSELECTIVE SYNTHESIS OF RAC-DIORGANOSILYLBIS(2-METHYLBENZO[E]INDEYL) ZIRCONIUM COMPONDS<br/>[FR] SYNTHESE RACEMOSELECTIVE DE COMPOSES DE RAC-DIORGANOSILYLBIS(2-METHYLBENZO[E]INDENYL)ZIRCONIUM
申请人:BASELL POLYOLEFINE GMBH
公开号:WO2004037840A1
公开(公告)日:2004-05-06
The present invention relates to a specific process for the diastereoselective synthesis of racy diorganosilylbis(2methylbenzo[e]indenyl)zirconium compounds of the formula I, by reacting the silyl-bridged bisindenyl ligand with a dihalozirconiumbis(3,5-di-tert-butylphenoxide)- base adduct to form the diorganosilylbis(2-methylbenzo[e]indenyl)zirconium bis(3,5-di-tert-butylphenoxide) and subsequently replacing the phenoxide groups by X using suitable replacement reagents to give the compound of the formula (I); where the substituents X can be identical or different and are each F, CI, Br, I or linear, cyclic or branched C1-10-alkyl; and the substituents R can be identical or different and are each linear, cyclic or branched C1-10-alkyl or C6-10-aryl; and also to the use of these compounds as catalysts.