1987 年 45 巻 1 号 p. 48-59
Organic molecules with polyhedral symmetry have been and remain a challenge to organic chemists. Among hydrocarbons based on Platonic solids, cubane (Oh symmetry) was prepared by Eaton and Cole in 1964 and dodecahedrane, which exhibits the highest symmetry (Ih) ever imagined for any organic compound, was made by Paquette and co-workers in 1982. Tetrahedrane (Td symmetry), the “simplest” of the Platonic hydrocarbons, is unknown but the tetralithio and the tetra-tert-butyl derivatives were prepared in 1978 by the Schleyer group and the Maier group, respectively. Among molocules with chiral polyhedral symmetry (T, O, and I symmetry), the existence of molecules with conformational T symmety has been discussed by several workers. The first experimental proof of the existence of the conformational T symmetry molecule was given by Bartell and co-workers in 1970. The synthesis of the first optically active organic molecule with T symmetry has been accomplished by our group in 1982. As far as I know, organic molecule belonging to the O and I point group is still unknown.