THE REACTION OF GROUP-14 DIMETALLENES WITH ALKENES - ELECTRON-POOR ALKENES

The addition reactions of tetramesitylgermasilene with methyl vinyl ke tone (MVK), crotonaldehyde, and acrylonitrile were studied. When tetra mesitylgermasilene was allowed to react with MVK, [2 + 4] cycloadditio n and nonregioselective carbonyl [2 + 2] cycloaddition products were i solated. When tetramesitylgermasilene was allowed to react with croton aldehyde, the carbonyl [2 + 2] adduct was produced exclusively. The re giochemistry was not determined. The addition of acrylonitrile to tetr amesitylgermasilene yielded a germasilacyclobutane, which is the forma l [2 + 2] cycloadduct between the germasilene and the C-C double bond of acrylonitrile. Tetramesityldisilene was also found to yield a forma l [2 + 2] adduct with acrylonitrile. However, tetramesityldigermene re arranges to a germylgermylene at a faster rate than acrylonitrile addi tion.