1,3,5-Triaza-7-phosphaadamantane (PTA): A Practical and Versatile Nucleophilic Phosphine Organocatalyst
作者:Xiaofang Tang、Bo Zhang、Zhengrong He、Ruili Gao、Zhengjie He
DOI:10.1002/adsc.200700071
日期:2007.8.6
cycloaddition reaction of 4-substituted 2,3-butadienoates with N-tosylimines, PTA is also proven to be a comparable catalyst as tributylphosphine (PBu3). By systematic comparison with other structurally similar N,P catalysts, it is concluded that the superiority of PTA in the above nucleophilic catalysis is attributable to its comparable nucleophilicity with that of trialkylphosphines. The feasibility
Ultrasound in Baylis–Hillman reactions with aliphatic and aromatic aldehydes: scope and limitations
作者:Fernando Coelho、Wanda P. Almeida、Demetrius Veronese、Cristiano R. Mateus、Elizandra C. Silva Lopes、Rodrigo C. Rossi、Gabriel P.C. Silveira、César H. Pavam
DOI:10.1016/s0040-4020(02)00822-0
日期:2002.9
The utilization of ultrasound radiation in the Baylis–Hillman reaction with several aldehydes (aromatics and aliphatics) and different α,β-unsaturated reactants is described. For all aldehydes tested, the utilization of ultrasound sources augmented the reactionrate and the chemical yields. The use of ultrasound with two different catalysts (tri-n-butylphosphine and 1,4-diazabicyclo[2.2.2]octane [DABCO])
The First Air-Stable and Efficient Nucleophilic Trialkylphosphine Organocatalyst for the Baylis–Hillman Reaction
作者:Zhengrong He、Xiaofang Tang、Yaoming Chen、Zhengjie He
DOI:10.1002/adsc.200505403
日期:2006.3
1,3,5,-Triaza-7-phosphaadamantane (PTA) is first reported to be a convenient and efficient nucleophilic trialkylphosphine organocatalyst for the Baylis–Hillman reaction. Thus, under the mediation of 15–20 mol % of PTA and practical conditions, both aromatic and aliphatic aldehydes react with the activated alkenes like acrylates and methyl vinyl ketone to afford the corresponding adducts in fair to
Traditional Morita–Baylis–Hillman reaction of aldehydes with methyl vinyl ketone co-catalyzed by triphenylphosphine and nitrophenol
作者:Min Shi、Ying-Hao Liu
DOI:10.1039/b600854b
日期:——
In the Morita-Baylis-Hillman reaction of aldehydes with methyl vinyl ketone (MVK), we found that in the presence of a catalytic amount of phenol, the Lewis base triphenylphosphine can effectively promote the reaction to give the corresponding normal Morita-Baylis-Hillman adducts in good yields. The mechanism has been investigated by 31P NMR spectroscopy. The solvent and substituent effects were also
在醛与甲基乙烯基酮(MVK)的Morita-Baylis-Hillman反应中,我们发现在催化量的苯酚存在下,路易斯碱三苯基膦可以有效地促进反应,从而产生相应的正常Morita-Baylis-Hillman加合物收率高。该机理已通过31 P NMR光谱进行了研究。还检查了溶剂和取代基的作用。
Reexamination of the traditional Baylis–Hillman reaction
作者:Min Shi、Chao-Qun Li、Jian-Kang Jiang
DOI:10.1016/s0040-4020(03)00041-3
日期:2003.2
In the Baylis-Hillman reaction of arylaldehydes with methyl vinyl ketone (MVK), we found that, besides the normal Baylis-Ellman adduct 1, the diadduct 2 can also be formed at the same time and the yield of 2 can reach to 55% if increasing the amount of methyl vinyl ketone. But for ethyl vinyl ketone (EVK), methyl acrylate or acrylonitrile, only the normal Baylis-Hillman adduct 4, 7 or 8 was obtained, respectively. The substituent's effects and Lewis base effects were also examined and a plausible reaction mechanism was proposed for the formation of 2. (C) 2003 Elsevier Science Ltd. All rights reserved.