The Synthesis of Phosphaisocoumarins by Cu(I)-Catalyzed Intramolecular Cyclization of <i>o</i>-Ethynylphenylphosphonic Acid Monoesters
作者:Ai-Yun Peng、Yi-Xiang Ding
DOI:10.1021/ja038627f
日期:2003.12.1
Cu(I)-catalyzed intramolecular cyclization of o-ethynylphenylphosphonic acid monoethyl esters was examined, and a new class of six-membered phosphorus heterocycles was formed with high regioselectivity and good yields. The present reaction is the first example of intramolecular addition of P-OH to alkynes, which provides a convenient way to synthesize novel phosphorus heterocycles having potential
Synthesis of 4-halophosphaisocoumarins via halocyclization of 2-(1-alkynyl)phenylphosphonates
作者:Ai-Yun Peng、Yi-Xiang Ding
DOI:10.1016/j.tet.2005.08.032
日期:2005.10
A series of 4-halophosphaisocoumarins were prepared with high regioselectivity in good to excellent yields under mild conditions by the reaction of 2-(1-alkynyl)phenylphosphonic acid diesters with I2 in CHCl3 or ICl in CH2Cl2, or by the reaction of 2-(1-alkynyl)phenylphosphonic acid monoesters with NBS or NCS in DMF. Whether the alkynylphosphonates could cyclize or not was affected by the substituents
A copper-catalyzed tandem carboarylation/cyclization of alkynyl phosphonates with diaryliodoniumsalts is reported. The reaction gives straightforward access to valuable cyclic enol phosphonates in good yields under mild conditions. This transformation entails an initial chemoselective arylation of the alkyne followed by an intramolecular trapping of an intermediate vinyl cation by the phosphoryl group
An Efficient Route to 4-Halophosphaisocoumarins via CuX<sub>2</sub>-Mediated Direct Halocyclization of 2-(1-Alkynyl)phenylphosphonic Acid Diesters
作者:Ai-Yun Peng、Fei Hao、Baojian Li、Zheng Wang、Yidan Du
DOI:10.1021/jo801842g
日期:2008.11.21
A series of 4-halophosphaisocoumarins were synthesized via CuX2 (X = Br, Cl) -mediated direct halocyclization of 2-(1-alkynyl)phenylphosphonic acid diesters in dichloroethane with the addition of n-Bu4NX or/and AgI in good to excellent yields. This reaction provides an efficient route to 4-halophosphaisocoumarins and represents the first example of bromo- and chlorocyclization of unsaturated phosphonic
4-bromophosphaisocoumarins underwent a dehalogenation–alcoholysis tandem reaction. The possible mechanism for the alcoholysis reaction was discussed. In addition, direct access to 2-(2-oxoalkyl)phenylphosphonates was developed by the mercury(II)-catalyzed hydration of 2-(1-alkynly)phenylphosphonates with high regioselectivity. In a preliminary study, the obtained novel keto phosphonates showed medium inhibitory