SYNTHESE ET REACTIVITE COMPAREE D'ALKOXY ET DE THIOALKOXYMETHYLENECETENES

Article abstract of DOI:10.1016/S0040-4039(00)82226-1

Heterosubstituted methyleneketenes 2d-g are obtained by flash-vacuum pyrolysis of Meldrum's acid derivatives 1d-g.The methoxymethyleneketene 2e is stable for a few hours at room temperature and gives 3e by dimerization; in contrast, the more reactive thiomethoxymethyleneketenes 2f-g are easily converted to 4f-g by intramolecular rearrangement.