CIDNP 1H study of the photolysis of 7-sila- and 7-germa-norbornadienes

Article abstract of DOI:10.1016/0022-328X(90)80163-T

The photochemical decomposition of 7-sila- and 7-germa-norbornadienes (1a,b) was studied by the CIDNP 1H technique.The reactions proceeds by a two-step mechanism via the reversible formation of singlet biradicals, II.The triplet biradical (II), formed as a result of S-T conversion of (II)(S), irreversibly decomposes giving Me2E (E = Si, Ge).The insertion of Me2E into the C-Br bond of PhCH2Br and the Sn-Cl bond of Me3SnCl occurs via a radical mechanism, as deduced from the CIDNP effects observed in these reactions.