非消旋连接的氢化铜可用于串联S N 2'/ 1,2-还原外消旋的森田-贝利斯-希尔曼(MBH)乙酸酯,以得到具有定义的烯烃几何形状的对映体富集的手性烯丙基醇。MBH酯(包括具有β取代基的酯)可以利用庞大的,低聚的,原位生成的三烷氧基硅氧烷离去基团转化为立体定义的烯酸酯。最后,公开了容易到达的MBH醇衍生物向非外消旋烯丙基醇的非典型转化。
作者:Hyunah Choo、Youhoon Chong、Kwang-Su Park、Jinyoung Kim
DOI:10.1055/s-2007-968032
日期:2007.2
The Baylis-Hillman reaction was greatly accelerated by use of octanol as an additive. Under the octanol-accelerated Baylis-Hillman conditions, unactivated aldehydes such as aliphatic aldehydes and aromatic aldehydes with electron-withdrawing substituents were readily converted into the desired products in good to high yields.
Switchable pyrrole-based hydrogen bonding motif in enantioselective trifunctional organocatalysis
作者:Sviatoslav S. Eliseenko、Fei Liu
DOI:10.1016/j.tet.2018.12.016
日期:2019.1
Pyrroles are versatile chemical motifs for molecular recognition or ligand design but their utility as catalytic components are underexplored. We incorporated a pyrrole motif into our acid-switchable, MAP-based trifunctional organocatalytic system. The switching-on of this system by an external Brønstedacid, 3-methyl benzoic acid, presented proficient catalysis in both aza-Morita–Baylis–Hillman (MBH
Chemoselectivity Improvement<i>via</i>Partial Shielding of an Imidazole Active Site in Branched/Dendritic Homogeneous Catalysts of the Baylis-Hillman Reaction
of providing partial shielding of this site. The design of the catalysts was based on a 5‐hydroxyisophthalate scaffold, and they were prepared through a number of multistep synthetic pathways. The comparison of the catalysts under a variety of conditions in a model Baylis–Hillman reaction demonstrated that long hydrophobic tales enhance the chemoselectivity parameter of the catalysis, while reducing
Studying the Morita-Baylis-Hillman Reaction in Continuous Flow Using Packed Bed Reactors
作者:Rasmus A. T. Verdier、Jesper H. Mikkelsen、Anders T. Lindhardt
DOI:10.1021/acs.oprd.8b00298
日期:2018.11.16
Conditions for the Morita-Baylis-Hillmanreaction were developed under continuous flow using a packed bed reactor carrying 4-(dimethylamino)pyridine immobilized on silica. High reaction rates were obtained, as the packed bed reactor mimics super-stoichiometric catalyst loadings for the passing reaction mixture. Catalyst deactivation was circumvented by avoiding acrylate esters as the reaction partners. The
First Evidence of Proline Acting as a Bifunctional Catalyst in the Baylis–Hillman Reaction Between Alkyl Vinyl Ketones and Aryl Aldehydes
作者:Michelangelo Gruttadauria、Francesco Giacalone、Paolo Lo Meo、Adriana Mossuto Marculescu、Serena Riela、Renato Noto
DOI:10.1002/ejoc.200701112
日期:2008.3
Proline in the presence of sodium hydrogen carbonate has been found to be an effective catalyst for the Baylis–Hillman reaction between methyl or ethylvinyl ketone and aryl aldehydes. Screening of several amine catalysts showed that an ionizable carboxylic function directly linked to the secondary amine catalyst plays an important role in the synthesis of the desired product in good yield. The data