Efficient Baylis–Hillman reactions promoted by mild cooperative catalysts and their application to catalytic asymmetric synthesis
作者:Yoichi M.A Yamada、Shiro Ikegami
DOI:10.1016/s0040-4039(00)00125-8
日期:2000.3
Baylis–Hillmanreactions were promoted by mild cooperative catalysts of tributylphosphine with phenols such as (±)-1,1′-bi-2-naphthol (BINOL) in THF to give α-methylene-β-hydroxyalkanones in high yield. The reactions proceeded much faster in the presence of 1,1′-bi-2-naphthol than in its absence. The 1H NMR studies suggested that 1,1′-bi-2-naphthol functions as a Brønsted acid to activate the carbonyl
三丁基膦与酚类的温和协同催化剂(例如(±)-1,1'-联-2-萘酚(BINOL)在THF中)促进了Baylis-Hillman反应,从而以高收率得到α-亚甲基-β-羟基链烷酮。在有1,1'-联-2-萘酚存在下,该反应进行得比在没有它的情况下进行得快得多。的1项1 H NMR研究表明,1,1'-联-2-萘酚用作布朗斯台德酸来激活醛和偏振烯烃的羰基。通过使用三丁基膦与钙手性催化剂的协同催化剂来检查反应在催化不对称合成中的应用,以相当好的收率得到具有相当好的%ee的所需产物。
Azobenzene-Tethered Bis(Trityl Alcohol) as a Photoswitchable Cooperative Acid Catalyst for Morita-Baylis-Hillman Reactions
作者:Tatsushi Imahori、Ryo Yamaguchi、Seiji Kurihara
DOI:10.1002/chem.201201383
日期:2012.8.27
Incorporation of an azobenzene core into tethered bis(tritylalcohol) allows the photoswitchable arrangement of the two tritylalcohol units through photoisomerization of azobenzene. The differently arranged tritylalcohol units change their cooperative function to reflect the positional relationships, and thus, the activity as a cooperativeacid can be controlled by light stimuli (see figure).
Merging metal–organic framework catalysis with organocatalysis: A thiourea functionalized heterogeneous catalyst at the nanoscale
作者:Yi Luan、Nannan Zheng、Yue Qi、Jia Tang、Ge Wang
DOI:10.1039/c3cy00864a
日期:——
A new thiourea-containing metalâorganic framework (MOF) catalyst was synthesized. It overcomes recycling, self-aggregation and solvation issues that exist in homogeneous thiourea catalysts. Nanomorphology was introduced to increase the dispersion of the solid catalyst in solvent. Acetalization and MoritaâBaylisâHillman reactions were catalyzed using the new thiourea MOF catalyst.
Development of a novel Brønsted acid UiO-66 metal–organic framework catalyst by postsynthetic modification and its application in catalysis
作者:Zongcheng Miao、Chao Qi、Allison M. Wensley、Yi Luan
DOI:10.1039/c6ra14365b
日期:——
A novel Bronsted acid derived metal-organicframework (MOF) has been developed to serve as an efficient heterogeneous catalyst for the acetalization and Morita-Baylis-Hillman reaction. Aromatic sulfonic acid groups were successfully...
Tributylphosphine or dimethylphenylphosphine (1-5 mol%) catalyzed the Morita-Baylis-Hillman reaction of 2-cyclopenten-1-one (1) with 1.2 equivalents of formalin proceeded nicely to give 2-hydroxymethyl-2-cyclopenten-1-one (2) within a short period and in an excellent yield. The efficiency of the reaction (yield and time) was strongly dependent on the solvent and the best result was obtained in the case of an aqueous MeOH-CHCl3 solvent system.