Reductive opening of phenyl substituted thiacycloalkanes: New way for sulphur-containing organolithium compounds

✍ Scribed by Juan Almena; Francisco Foubelo; Miguel Yus

• Book ID: 104207724
• Publisher: Elsevier Science
• Year: 1997
• Tongue: French
• Weight: 632 KB
• Volume: 53
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(97)00211-1

✦ Synopsis

The reaction of 2-phenyl substituted four, five and six membered thiacycloalkanes (1, 4 and 7) with lithium and a catalytic amount of DTBB (5 mol %) in THF at -78°C leads to the corresponding sulphur-containing benzylic organolithium compounds (2, 5 and 8), which by reaction with different electxophiles [D20, Me3SiCI, ButCHO, Me2CO, Et2CO, (CH2)4CO, CO21 followed by hydrolysis with water afford the expected functionalised mercaptans (3, 6 and 9) in a regioselective manner. Some reaction products (3, 6) are cyclised under acidic conditions (85% phosphoric acid) to yield the corresponding homologous substituted sulphur-containing saturated heterocycles (10, 11).