Effective Synthesis of ortho ‐Substituted Trithiophenol Amines by Miyazaki–Newman–Kwart Rearrangement

An efficient synthesis of ortho ‐substituted trithiophenol amines from commercially available salicaldehydes by Miyazaki–Newman–Kwart rearrangement/threefold reductive amination is reported. The rearrangement has been carried out on salicaldehyde‐ O ‐thiocarbamates using microwave induced heating, which furnishes a series of thiosalicaldehyde‐ S ‐carbamates in high yield. The thiocarbamate has three roles: it enables effective S – O rearrangement, acts as a protecting group during the threefold reductive amination and can be easily removed under reductive conditions. The three‐step synthesis has an overall yield ranging from 30–35 %, and it enables access to a series of increasingly important C 3 v symmetric ligands in a structurally systematic way.