M. Neuenschwander, C. Bacilieri
Jun 7, 2000
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0
Influential Citations
2
Citations
Journal
Helvetica Chimica Acta
Abstract
Surprising Reaction of 5-(Phenylthio)- and 5-(Methylthio)pent-2-en-4-inal with HCl Contrary to expectations (Scheme 1), 5-(phenylthio)-(1a) as well as 5-(methylthio)pent-2-en-4-inal (1b) react with a slight excess of HCl to give 2-[bis(phenylthio)methyl]furan (17a, 77% yield) and 2-[bis(methylthio)methyl]furan (17b, 61% yield), respectively. Structures 17a and 17b are supported by the results of an X-ray crystal-structure analysis, by spectroscopic data in comparison to those of model compounds, and by synthesis of 17a. This surprising reaction is tentatively explained by a mechanism (Scheme 4), including a special pyranfuran ring-contraction sequence, which is in agreement with a labelling experiment.