Preparation of C70H2, C70H4, and C70H8: Three independent reduction manifolds in the Zn(Cu) reduction of C-70

This article reports the preparation of C70Hn species by Zn(Cu) reduction. The major products were one isomer of C70H2, one major isomer of C70H4, and one major isomer of C70H8. Several minor products were detected by UV-Vis and/or mass spectrometry. The structures of the major products were assigne d as 1,2-C70H2, 1,2,56,57-C70H4, and 7,19,23,27,33,37,44,53-C70H8. Interest ingly, although the major isomer of C70H4 is generated by reduction of the major isomer of C70H2, the major isomer of C70H8 is not generated by reduct ion of the major isomer of C70H2 or C70H4 The evidence suggests that there are at least three different reduction manifolds operating. One manifold in cludes 1,2-C70H2 and 1,2,56,57-C70H4, major products in which highly pyrami dalized bonds near the poles of C-70 are reduced. A second manifold include s 5,6-C70H2, a minor product. The third manifold consists of a set of C70H2 , C70H4, and C70H6 species that are highly reactive and do not accumulate i n solution. This third manifold leads to 7,19,23,27,33,37,44,53-C70H8. This third manifold is unique in that these compounds place hydrogens on nonadj acent carbons, a previously unobserved arrangement.