A process for preparing lacidipine, comprising reacting a t-butoxy carbonyl methyl aryl phosphonium halide with o-phthalaldehyde, and further reacting a product comprising (E)-3-(2-formylphenyl)-2-propenoic acid, 1,1-dimethyl ethyl ester, without isolation, with ethyl-3-amino crotonate.
Soluble poly(ethylene glycol) (PEG)-supported telluride 2 was designed and synthesized for catalytic Wittig-type reactions. It was found that the catalytic loading could be reduced from 20 to 2 mol % by the introduction of PEG (even to 0.5 mol % when some telluride salts were used as the catalyst). Under the catalytic reaction conditions, a wide variety of aldehydes with different structures could
Soluble PEG-supported telluride 2 was synthesized and found to be an effective catalyst for the catalytic Wittig-typereaction to give a variety of α,β-unsaturated esters in high yields with excellent E-stereoselectivity in the presence of sodium bisulfite as well as triphenyl phosphite.
A Facile, One-Pot Synthesis of Lacidipine Using in Situ Generation of Wittig Intermediates
作者:V. V. N. K. V. Prasada Raju、Vedantham Ravindra、Vijayavitthal T. Mathad、P. K. Dubey、Padi Pratap Reddy
DOI:10.1021/op900055u
日期:2009.7.17
An improved, one-pot process for the preparation of lacidipine (1) via an efficient in situ generation of Wittig intermediates is reported. Generation of ylide (4) by dehydrobromination of phosphonium salt (3) followed by in situ condensation of 4 with o-phthalaldehyde (5) to yield corresponding olefin (6) and its subsequent reaction with crotonate derivative (7) in the same pot furnished the drug
作者:Steven D. Bull、Stephen G. Davies、Andrew D. Smith
DOI:10.1039/b107440g
日期:2001.11.15
Addition of two or three equivalents of lithium (S)-N-benzyl-N-α-methylbenzylamide to conjugate acceptors containing two or three α,β-unsaturated ester fragments respectively and subsequent hydrogenolytic deprotection afford homochiral bis- or tris-β-amino esters containing two or three new stereogenic centres in high de and ee.