Pyridinium Ylides Derived from Pyryliums and Amines and a Novel Rearrangement of 1-Vinyl-1,2-dihydropyridines

Article abstract of DOI:10.1021/jo00342a024

1-Benzyl-2,4-diphenylpyridiniums with benzaldehydes give oxazolopyridines which are dehydrated to 1-styryl derivatives.On pyrolysis the 1-styryl-1,2-dihydropyridine 21a gave 2,4,6-triphenylpyridine and m-chlorostyrene by a ring-enlargement-ring-contraction mechanism: this is a general reaction of 1-vinyl-1,2-dihydropyridines.