Abstract
The first Barton–Kellogg olefination employing thioamides or thioureas as substrates is reported. Starting from the conjugated dithioxo compounds 1 and diazocompounds 2 we substituted the C˭S groups by ester substructures mono- (type 3) and obtained the disubstituted products 4. Using the same procedure, the tricyclic thiourea 5 was converted into a new ketene aminal 6. Intermediates such as primary cycloadducts or three-membered ring-contraction products could not be isolated for any reactions studied here.
The supports of the Deutsche Forschungsgemeinschaft (SFB 436), Roche Diagnostics GmbH (Penzberg, Germany) and the Fonds der Chemischen Industrie are gratefully acknowledged.