A Facile One-Pot Synthesis and Temperature Dependence of NMR Spectra of Stable Heterocyclic Phosphorus Ylids

Abstract

The addition of dialkyl acetylenedicarboxylates to isatin, a strong NH acid, in the presence of triphenylphosphine leads to stable crystalline phosphorus ylids in excellent yields and one of the three synthesised compounds (3a) exists as a mixture of two rotational isomers on the basis of variable temperature nmr spectroscopy.

Keywords

acetylenic esters triphenylphosphine NH-acids organophosphorus compounds

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