Synthetic Approaches to ( Z )‐Thioaurones

( Z )‐Thioaurones were prepared by the condensation of 1‐benzothiophen‐3‐ones or 3‐acetoxybenzothiophene with arylaldehydes under basic or acidic conditions. Their derivatives were also prepared by reducing 2‐benzoybenzothiophen‐3‐ones and subsequent dehydration, cyclization of α,β‐unsaturated 1‐(2‐methylsulfinyl)phenyl ketone, and coupling of β‐chlorobenzothiophenone with arylboronic acids using Pd catalyst. Furthermore, ( Z )‐thioaurones were prepared by the direct cyclization of α‐(phenylthio)cinnamic acids, 5‐ exo cyclization of 2′‐(methylthio)chalcones, incorporation of a sulfur atom to 2′‐nitrochalcones and aromatic substitution, and deprotection of S ‐protected alkynones and subsequent cyclization. Moreover, thioflavanone‐1‐oxides underwent ring contraction with I 2 or NaOAc/Ac 2 O to give ( Z )‐thioaurones.