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DOI: 10.1055/s-1992-34150
Directed ortho Metalation of O-Aryl and O-Pyridyl Thiocarbamates. A Versatile Synthetic Method for Substituted Phenol into Thiophenol Conversion
Publikationsverlauf
Publikationsdatum:
18. September 2002 (online)

The preparation of ortho-substituted O-aryl and O-pyrid-3-yl thiocarbamates 7a-h and 11a-d and anionic ortho-Fries rearrangements of selected cases, [O-phenyl N,N-diethylthiocarbamate (6a) → N,N-diethyl-2-hydroxy-3-methylbenzenecarbothioamide (9), O-[4-(trimethylsilyl)pyridyl-3-yl] N,N-diethylthiocarbamate (11a) → N,N-diethyl-3-hydroxy-4-(trimethylsilyl)pyridine-3-carbothioamide (13)], via the directed ortho metalation protocol are described; coupled with their further thermal conversion (Kwart-Newman rearrangement) into S-thiocarbamate 8a-f and 12a-b and simple hydrolysis, this constitutes a new methodology for phenol to ortho-substituted thiophenol conversion (4 → 5).