“Novel synthesis of cyclic methylvinylsiloxanes by the reaction of methylvinyl diethoxysilane with phosphorous pentachloride”

ANDRÉS CIOLINO, BRUNO M. VUANO, OLGA PIERONI, MARCELO A. VILLAR AND ENRIQUE M. VALLÉS

JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY

John Wiley & Sons

Lugar: New York (USA); Año: 2002 p. 3182 - 3189

0887-624X

Abstract: We report a novel synthesis of the cyclic oligomers [(H2C=CH)(CH3)SiO]n obtained by the reaction between phosphorous pentachloride and methylvinyl diethoxysilane. According to gas chromatography/mass spectrometry data, the reaction product consisted of a mixture of cyclic oligomers in which the most important fractions were composed of cycles with n = 5, 6, or 7. The reaction product was also characterized by Fourier transform infrared and 1H and 13C NMR spectroscopy. Experimental results suggested a new kind of reaction between the phosphorous pentachloride and terminal olefins directly bonded to silicon, which was probably associated with sterical effects favoring COSi bond cleavage of ethoxy groups instead of the conventional addition of phosphorous pentachloride to olefinic linkages.