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F. Sauter, U. Jordis, G. Cai:
"Dehydrogenation of 2-ethylbenzenethiols: improved synthesis of benzo[b]thiophenes";
Journal of Chemical Research, Synopses, 11 (1983), 276.

The known procedure (Hansch, C.; et al., 1956) for the prepn. of benzo[b]thiophenes I (R = H, NH2) by catalytic dehydrogenation of 4,3-Et(HS)C6H3R (R as before) is improved by the use of readily accessible catalysts. These were Cu-Cr on activated charcoal or BASF catalysts V-1283 and H 3-10. The dehydrogenation app. (H.; 1953) is simplified by use of an infusion pump. I (R = H, NH2) were obtained in £73% and £65.2% yield, resp.