THE FIRST 1,4,2-OXATHIAZOLIUM SALTS: REMARKABLE SIMILARITIES TO THEIR 1,3,4-ISOMERS

Article abstract of DOI:10.1016/S0040-4039(00)92162-2

5-Methylmercapto-1,4,2-oxathiazoles, formed by 1,3-dipolar cyclo-addition between nitrile oxides and methyl dithiocarboxylates, are readily solvolysed with strong acid and acyl anhydride to give in high yields the first examples of 1,4,2-oxathiazolium salts.Remarkable similarities between the 13C NMR spectra of these and identically-substituted 1,3,4-oxathiazolium salts suggest that electronically the structures of the isomeric cations are very close.Key Words: 1,4,2-Oxathiazolium; 1,3,4-Oxathiazolium; 1,4,2-Oxathiazole; 1,3-Dipolar Cycloaddition;13C NMR spectra.