NEW DIGERMANES - AN ATTEMPTED SYNTHESIS OF A DIGERMADIENE

1,2-Dimesityltettachlorodigermane 7 has been prepared by chlorination of 1,2-dimesityldigermane 6 with CCl4. From 7, four new digermanes Mes (CHR2)Ge(X)Ge(X)(CHR2)Mes (CHR2 = fluorenyl; X = H (4), Cl (5), OH (8) or F (9)) have been synthesized. These sterically crowded derivatives are obtained as two diastereoisomers which have been isolated in the pure state by fractional crystallization. Reactions of various lithio compounds with the chloro or fluoro derivatives 5 or 9 lead to fluoren e, following lithium-halogen exchange and then alpha-elimination and, in the case of (t)BuLi, a reduction of the germanium-halogen bond.