Abstract Heptafulvenone (1), vinylketene (11), 1, 3-butadienylketene [(E)-15], and allenylketene (21) have been prepared by reaction of the corresponding acyl chlorides with 1, 8-bis (dimethylamino) naphthalene as long-lived species in solution at room temperature, and their ketenyl IR bands observed under these conditions for the first time, at 2101, 2118, 2111, 2117 cm− 1, respectively. These unsaturated ketenes react with ...
