Adducts of sila-, germa-, and stannaethenes Me<sub>2</sub>E=C(SiMe<sub>3</sub>)<sub>2</sub> (E = Si, Ge, Sn) with anthracene: syntheses, structures, thermolyses
The [4 + 2] cycloadducts of Me2E=C(SiMe3)2 (E = Si, Ge, Sn) and anthracene are prepared by reaction of an excess of anthracene in benzene with the [2 + 2] cycloadduct of Me2Si=C(SiMe3)2 and Ph2C=NSiMe3 at 130°C, with Me2Ge(OPh)-CLi(SiMe3)2 at 100°C, and with Me2SnBr-CNa(SiMe3)2 at 80°C, respectively. The mentioned adducts act as sources for the ethenes Me2E=C(SiMe3)2 above 100°C, the intermediate formation
Dimere der Ethene Me2EC(SiMe3)2 (E=Si, Ge, Sn): Auf welchem Wege entstehen sie aus Me2EXCM(SiMe3)2? Wie sind sie strukturiert?
作者:N. Wiberg、T. Passler、S. Wagner、K. Polborn
DOI:10.1016/s0022-328x(99)00727-5
日期:2000.4
(e.g. pentane, diethyl ether, tetrahydrofuran) (i) by a very fast Br/M exchange into the ‘metalation products’ Me2EXCM(SiMe3)2, which thermolyze under formation of ‘cyclobutanes’ [Me2EC(SiMe3)2]2, and (ii) to a lesser extent by X/R exchange into ‘substitution products’ Me2ERCBr(SiMe3)2. As shown by trapping experiments, the unsaturatedcompounds Me2EC(SiMe3)2 play the role of short-lived intermediates