Rhodium-catalyzed highly selective thioformylation of acetylenes with thiols and carbon monoxide

✍ Scribed by Jun-ichi Kawakami; Mitsuhiro Takeba; Ikuyo Kamiya; Noboru Sonoda; Akiya Ogawa

• Book ID: 104205631
• Publisher: Elsevier Science
• Year: 2003
• Tongue: French
• Weight: 204 KB
• Volume: 59
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(03)01061-5

✦ Synopsis

Highly regioselective thioformylation of terminal acetylenes with thiols and carbon monoxide has been developed by the use of rhodium(I) complexes as the catalyst: formyl and thio groups are introduced into the terminal and inner positions of acetylenes, respectively. The thioformylation is performed in the presence of a catalytic amount of rhodium(I) complexes, such as RhH(CO)(PPh 3 ) 3 , RhCl(PPh 3 ) 3 , and RhCl(CO)(PPh 3 ) 2 , under the pressure of CO (3 MPa) at 1208C in CH 3 CN to provide b-thio-a,b-unsaturated aldehydes in good yields. This thioformylation can be applied to a variety of terminal acetylenes and aromatic thiols. A mechanistic proposal includes the formation of the rhodium sulfide complex as the key species.