(Nitroary1) sulfiiyl-substituted allenes are conveniently prepared by treating propargyl alcohol or methyl 3-hydroxy-2-butynoate with a (nitroary1) sulfenyl chloride and triethylamine. These activated allenes undergo 4+ 2 cycloaddition the C1C2%-bond. The initially formed allylic sulfoxide readily undergoes a 2, 3-aigmatropic rearrangement to produce a stable sulfenate eater that ie eanily cleaved with thiophilic magenta. The ...
