
%0 Journal Article
%A Baxter, GJ 
%A Brown, RFC 
%A Eastwood, FW 
%A Gatehouse, BM 
%A Nesbit, MC 
%T Methyleneketenes and methylenecarbenes. XIII. Cycloaddition of ketenes and of a 1-pyrroline 1-oxide to isopropylideneketene
%J Australian Journal of Chemistry
%D 1978/08/01
%V 31
%N 8
%P 1757-1767
%K 
%R https://doi.org/10.1071/CH9781757
%U https://www.publish.csiro.au/paper/CH9781757 
%X Isopropylideneketene (3-methylbuta-1,2-dien-1-one), Me2C=C=C=O, reacts with ketene and substituted ketenes to give oxetanones or cyclobutane-1,3-diones formed by [2+2] cycloadditions involving the central C=C bond of the methyleneketene. By contrast Me2C=C=C=O reacts with 5,5- dimethylpyrroline 1-oxide to give a spirooxazolidinone (13) and an oxetanone (17), both of which appear to be formed by initial cycloaddition of the pyrroline 1-oxide to the terminal C=C bond of the methyleneketene and formation of an intermediate bicyclic ketene (15). The structure of the oxetanone (17) has been confirmed and its stereochemistry established by X-ray crystallography. 
