HETERO-PI-SYSTEMS - 25 - SILYLENES OF THE ELEMENTAL COMPOSITION C2H4SI2 - GENERATION AND MATRIX-SPECTROSCOPIC IDENTIFICATION

Pulsed flash pyrolysis in combination with matrix isolation of three p recursor molecules (10, 11, 12) led to the formation of silylsilacyclo propenylidene (1), which was identified by comparison of experimental and calculated (BLYP/6-31G) IR spectra for both, unlabeled 1 and its perdeuterated isotopomer. Upon irradiation of matrix-isolated silyl-si lacyclopropenylidene (1) a second C2H4Si2 isomer, namely (silylethynyl )silylene (4) was formed. However, no evidence could be found for the formation of disilatetrahedrane or 1,2- or 1,3-disilacyclobutadiene.