Reaction of perfluoro-2-methylpent-2-en-3-yl isothiocyanate with ethyl andisopropyl alcohols

Perfluoro-2-methylpent-2-en-3-yl isothiocyanate reacts with ethyl or isopro pyl alcohols in the presence of NEt3 to give derivatives of 4,5-dihydrothia zole and ethoxy(ethylthio)methylene-(1,1,1,4,4,5,5,5-octafluoro-2-trifluoro methylpent-2-en-3-yl)amine and isopropoxy(isopropylthio) methylene-(1,1,1,4 ,4,5,5,5-octafluoro-2-trifluoromethylpent-2-en-3-yl)amine, respectively. He ating of ethyl or isopropyl N-(pefluoro-2-methyl-2H-pentylidene-3-amino)thi ocarbamate with potassium carbonate in DMF yields the same products plus 3- tetrafluoroethylidene-5,5-bis(trifluoromethyl)thiazolidin-2-one. The struct ure of the latter was confirmed by X-ray diffraction analysis. The IR spect roscopy data for this compound in solution (CCl4) and in the solid state (K Br) suggest the formation of the intermolecular NH...O=C hydrogen bond betw een the NH group and the oxygen atom of the heterocycle.