Regioselective Synthesis of 3-Carbo-5-phosphonylpyrazoles through a One-Pot Claisen-Schmidt/1,3-Dipolar Cycloaddition/Oxidation Sequence
作者:Anthony R. Martin、Kishor Mohanan、Loic Toupet、Jean-Jacques Vasseur、Michael Smietana
DOI:10.1002/ejoc.201100167
日期:2011.6
A one-pot reaction involving an aldehyde, a methyl ketone, and the Bestmann-Ohira reagent has been developed for the synthesis of variously substituted 3-carbo-5-phosphonylpyrazoles. Our synthetic methodology features a domino Claisen- Schmidt/1,3-dipolar cycloaddition/oxidationsequence,which leads to the target compounds in excellent yields. We further demonstrated that this unprecedented sequence