Zum thermischen Verhalten einiger Kohlensäure[(methylphenylsilyl)methyl]ester-Derivate

Abstract

Abstract The synthesis and the thermal behaviour of the (methylphenylsilyl)methyl carbonates CH3(C6H5)Si(H)CH2OC(O)X (6: X = OCH3; 7: X = Cl; 8: X = N(CH3)2) is described. 8 rearranges in toluene solution at 100 °C quantitatively to give the carbam oyloxysilane C6H5(CH3)2SiOC(O)N(CH3)2 (11), whereas neat 6 and 7 at 135 °C undergo quantitative formation of C6H 5(CH3)2SiOCH3 (12) and C6H5(CH3)2SiCl (13), respectively. The formation of 12 and 13 is explained by a rearrangement reaction (by analogy to the rearrangement of 8), follow ed by a decarboxylation. The thermally induced transformations 6 →12, 7 →13, and 8 →11 were found to be first-order reactions with half-lifes of ~2.6 h (135 °C, neat), ~4.5 h (135 °C, neat), and ~3.7 h (100 °C, in toluene), respectively.