Synthesis of allenes by double Horner–Wadsworth–Emmons reaction
摘要:
LDA treatment of aldehydes or ketone with alkenylphosphonates 2, prepared by Horner-Wadsworth-Emmons (HWE) reaction of methylenebisphosphonate I with aldehydes, afforded Baylis-Hillman reaction-type products 5 in high yields. HWE olefination of 5 with KH or KH-18-crown-6 as a base provided allenes in good yields. One-flask procedure was successfully developed starting from I to afford an allene in a reasonably good yield. (C) 2002 Elsevier Science Ltd. All rights reserved.
Stereoselective synthesis of vinylphosphonates and phosphine oxides via silver-catalyzed phosphorylation of styrenes
作者:Qingwen Gui、Liang Hu、Xiang Chen、Jidan Liu、Ze Tan
DOI:10.1039/c5cc04826e
日期:——
An efficient and stereoselectivesynthesis of vinylphosphonates and phosphine oxides was developed starting from styrenes using AgNO3 as the catalyst and K2S2O8 as the oxidant. Various vinyl-phosphonates and phosphine oxides were synthesized in good yields with excellent regioselectivity.
从苯乙烯开始,使用AgNO 3作为催化剂,K 2 S 2 O 8作为氧化剂,开发了一种有效的立体选择性合成乙烯基膦酸酯和氧化膦的方法。以良好的产率和优异的区域选择性合成了各种乙烯基膦酸酯和氧化膦。
Copper-Catalyzed C-P Coupling through Decarboxylation
作者:Jie Hu、Ning Zhao、Bin Yang、Ge Wang、Li-Na Guo、Yong-Min Liang、Shang-Dong Yang
DOI:10.1002/chem.201003561
日期:2011.5.9
developed by copper‐catalyzed decarboxylative coupling of alkenyl, alkynyl carboxylic acids, and N‐benzylproline, respectively, with R2P(O)H (see scheme). All classes of products are important precursors for preparation of biologically active molecules and various phosphorus ligands. This finding represents the first example of copper‐catalyzed decarboxylative coupling to construct CP bonds.
An efficient and stereoselective procedure for the preparation of E-1-alkenylphosphonates by copper-mediated cross-coupling between 1,1-dibromo-1-alkenes and dialkyl phosphites is reported. The reaction allows for formal substitution of both bromine atoms, respectively, by an hydrogen and a dialkoxyphosphoryl.
Experimental and theoretical studies on nickel–zinc-catalyzed cross-coupling of <i>gem</i>-dibromoalkenes with P(O)–H compounds
作者:Liu Leo Liu、Ye Lv、Yile Wu、Xiang Gao、Zhiping Zeng、Yuxing Gao、Guo Tang、Yufen Zhao
DOI:10.1039/c3ra45212c
日期:——
A new stereoselective one-pot protocol for the preparation of E-alkenyl-phosphorus compounds under catalysis of an inexpensive nickel–zinc catalyst system has been developed, which provides a potential useful method for C–P bond formation.
Copper-Mediated Selective Cross-Coupling of 1,1-Dibromo-1-alkenes and Heteronucleophiles: Development of General Routes to Heterosubstituted Alkynes and Alkenes
site-selective, double, or alkynylative cross-coupling, therefore providing divergent and straightforward entries to numerous building blocks such as bromoenamides, ynamides, ketene N,N-acetals, bromoenol ethers, ynol ethers, keteneO,O-acetals, or vinylphosphonates and further expanding the copper catalysis toolbox with useful and versatile processes.