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.
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.
Nickel(II)-Magnesium-Catalyzed Cross-Coupling of 1,1-Dibromo-1-alkenes with Diphenylphosphine Oxide: One-Pot Synthesis of (<i>E</i>)-1-Alkenylphosphine Oxides or Bisphosphine Oxides
A novel nickel(II)‐magnesium‐mediated cross‐coupling of diphenylphosphine oxide with a variety of 1,1‐dibromo‐1‐alkenes has been developed, which provides a powerful and general methodology for the stereoselectivesynthesis of various (E)‐1‐alkenylphosphine oxides or bisphosphine oxides, with operational simplicity of the procedure, good to high yields and broad substrate applicability. Mechanistic
A new synthesis of π-electron conjugated phosphonates and phosphonic bis(diethylamides) and their SHG activities
作者:Takuji Ogawa、Naoya Usuki、Noboru Ono
DOI:10.1039/a709082j
日期:——
A series of vinylic and arylic phosphonates and phosphonic bis(diethylamides) were prepared by copper promoted substitution of the corresponding bromides. These Ï-electron conjugated phosphonates and phosphonic bis(diethylamides) were investigated to elucidate their optical and second harmonic generation (SHG) properties; it was found that diphenyl 2-(4-dimethylaminophenyl)ethenylphosphonate exhibited strong SHG activity, the efficiency being 13 times greater than that of urea.