首次证明了通过H键合亚胺离子形成的Morita–Baylis–Hillman醇的有机催化活化作用。这种激活策略使Morita-Baylis-Hillman醇能够进行正式的S N 2'反应。结合已建立的烯胺反应性,可创建新的反应模式。证明了这种新的活化方式在合成双环α-亚烷基-酮中的应用。发达的反应序列可以高效地进行,从而以高度立体选择性的方式为自然灵感的目标产物提供了四个连续的立体发生中心。
Mild and Efficient Iodine-Catalyzed Direct Substitution of Hydroxy Group of Alcohols with C- and N-Nucleophiles
作者:Zhe Liu、Dong Wang、Yongjun Chen
DOI:10.2174/157017811794557787
日期:2011.1.1
A mild and efficient iodine-catalyzed directsubstitution of hydroxygroup of allylic, progargylic and other alcohols with various C- and N-nucleophiles was described in this contribution. C-C and C-N bond formations could be readily achieved by non-metallic and green catalysis for various compounds. This facilitates access to possible transformations of a broad scope of substrates into bioactive and
Efficient Baylis−Hillman Reactions of Cyclic Enones in Methanol As Catalyzed by Methoxide Anion
作者:Sanzhong Luo、Xueling Mi、Hui Xu、Peng George Wang、Jin-Pei Cheng
DOI:10.1021/jo0491760
日期:2004.11.1
The Baylis−Hillman reactions of cyclic enones with a variety of aldehydes were investigated. 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) was found to be a viable catalyst in promoting the reactions of sterically retarded substrates in methanol. The reactions showed clear solvent dependence and only occurred in hydroxylic solvents, especially in methanol. Further consideration on the steric character of
Remarkable Rate Acceleration of Imidazole-Promoted Baylis−Hillman Reaction Involving Cyclic Enones in Basic Water Solution
作者:Sanzhong Luo、Peng George Wang、Jin-Pei Cheng
DOI:10.1021/jo035345p
日期:2004.1.1
The Baylis−Hillmanreaction of cyclic enones was greatly accelerated in basic water solution with imidazoles as catalysts, which resulted in short reaction time, high yields, and expanding substrate scopes. Bicarbonate solution was shown to be the optimal reaction medium for the reaction in this study. The apparent “enhanced basicity” of imidazoles accounted for the rate increase in alkaline solution
Lewis Base Effects in the Baylis−Hillman Reaction of Arenecarbaldehydes and N-Arylidene-4-methylbenzenesulfonamides with α,β-Unsaturated Cyclic Ketones
and 2-cycloocten -1- one in methanol, products 10 - derived from Michaeladditions of methanol to 9-were formed as the major products, along with traces of 9. In general, the ring-size of the α,β-unsaturated cyclic ketone can significantly affect the reaction products and rates, the Baylis-Hillman reaction and the aldolcondensation reaction taking place at the same time for 2-cyclohexen-1-one or 2-cyclohepten-1-one
Baylis-Hillman Reaction
of Cyclic Enones with Arenecarbaldehydes and <i>N-</i>Arylidene-4-methylbenzenesulfonamides
by Using NAP-MgO
作者:M. Kantam、L. Chakrapani、B. Choudary
DOI:10.1055/s-2008-1077959
日期:——
Baylis-Hillman reaction of cyclic enones with arenecarbaldehydes and N-arylidene-4-methylbenzenesulfonamides under mild conditions by using nanocrystalline MgO (NAP-MgO) afforded the Baylis-Hillman adducts in moderate to good yields with higher selectivity than the corresponding aldol products.