M. Shanta, R. M. Scrowston
1967
Citations
0
Influential Citations
7
Citations
Journal
Journal of The Chemical Society C: Organic
Abstract
5-Chloro- and 5-bromo-benzo[b]thiophen-3-carbaldehydes were prepared from the corresponding 3-bromomethyl compound, either by the Sommelet reaction (65% yield) or by the Krohnke reaction (30% yield). They had the usual properties of an aromatic aldehyde; in particular, they underwent the Doebner reaction with malonic acid, and formed crystalline condensation products with rhodanine.Friedel–Crafts acetylation of 5-chloro- or 5-bromo-benzo[b]thiophen gave predominantly the 3-acetyl derivative. This reacted with dimethylamine hydrochloride and formaldehyde (Mannich reaction) to give the corresponding keto-amine, the keto-group of which was reduced with sodium borohydride. The resulting alcohols were treated with thionyl chloride to give the corresponding substituted 3-chloropropylamines.