Metallation reactions. XXVI. α,α′-Dimetallation of 1,2-bis(methylthiobenzene)

• Published in: Tetrahedron Vol. 55; no. 49; pp. 14069 - 14078
• Main Authors: Cabiddu, M.G., Cabiddu, S., Cadoni, E., De Montis, S., Fattuoni, C., Melis, S., Sotgiu, F.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 03-12-1999
• Subjects: 1,2-bis(methylthio)benzene; benzodithiepins; dimetallation; thioethers; dimetallation; benzodithiepins; 1,2-bis(methylthio)benzene; thioethers
• ISSN: 0040-4020; 1464-5416
• DOI: 10.1016/S0040-4020(99)00873-X

Direct α, α′-dimetallation of 1,2-bis(methylthio)benzene allows the simultaneous introduction of equal or different electrophiles in thiomethyl groups and opens a new route to synthesise seven membered heterocycles.
α,α′-Dimetallation of bis(methylthio)benzene (
1) with butyllithium or with superbases gives
2 with good yield. This species allows the simultaneous introduction of two electrophiles in thiomethyl groups. Alternatively it was possible to functionalize these groups with two different electrophiles by two successive one-flask monometallations. Compound
2 rise to gives heterocyclic compounds.