Disilyloxydienes (2a-c) were easily obtained by treatment of stable sulfur yliders (1a-c) with chlorotrimethylsilane in the presence of triethylamine. Cycloaddition reaction of these dienes with some dienophiles was carried out.
The reaction of dimethylsulfonium acetylcarbamoylmethylide (Ia) with quinoline 1-oxide in the presence of acetyl chloride in N, N-dimethylformamide gave 6-methyl-5-methylthio-2-[2(1H)-quinolylidene]methyl-1, 3-oxazin-4-one (IIIa) and 6-methyl-5-methylthio-2-[2(1H))quinolylidene-2-quinolyl]methyl-1, 3-oxazin-4-one (IVa). The structures of IIIa and IVa were established by chemical and spectral analysis. This is a new type of reaction of stable sulfur ylides.