The first bicyclo[2.2.0]hexasilane, decaisopropylhexasilabicyclo[2.2.0]hexane was synthesized by the co-condensation of 1,1,2,2-tetrachlorodi-isopropyldisilane and 1,2-dichlorotetraisopropyldisilane with lithium in tetrahydrofuran.
Synthesis, structures, and oxidation of the ladder oligosilanes, such as bicyclo[2.2.0]hexasilane, tricyclo-[4.2.0.02,5]octasilane, tetracyclo[4.4.0.02,5.07,10]decasilane, and pentacyclo[6.4.0.02,7.03,6.09,12]dodecasilane, are reported.
The photolysis of tricyclic ladder oligosilanes gave a cyclotetrasilene intermediate, which was trapped by methanol, 2,3-dimethyl-1,3-butadiene, and anthracene. Anthracene underwent a cycloaddition with the cyclotetrasilenes at the 9,10- and 1,4-positions depending on the substituents on the cyclotetrasilene rings.