C−C Coupling Reactions of (Sulfene)ruthenium Complexes with Enolates

✍ Scribed by Wolfdieter A. Schenk; Jürgen Bezler

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 523 KB
• Volume: 1998
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/(sici)1099-0682(199805)1998:5<605::aid-ejic605>3.0.co;2-h

✦ Synopsis

Sulfene complexes [CpRu(PRЈ 3 ) 2 (RHC=SO 2 )]PF 6 (2aϪd) are obtained from the corresponding sulfur dioxide complexes 1aϪc and diazomethane or -ethane. Reaction of [CpRu(dppm)(SO 2 )]Cl (1d) and phenyldiazomethane gives the chlorobenzylsulfinato complex [CpRu(dppm)(SO 2 -CHPhCl)] (3). Alternatively, 2a may be synthesized by sulfur dioxide addition to the carbene complex [CpRu(dppm)-(CH 2 )]PF 6 (5) which, in turn, is obtained from the corresponding methyl complex [CpRu(dppm)(CH 3 )] and [Ph 3 C]PF 6 .

Highly reactive and unstable molecules can often be stabilized by coordination to a transition metal Ϫ this principle is certainly one of the most fascinating aspects of organic transition-metal chemistry. [1] In an ideal case, the species under consideration is not only "tamed", but is sufficiently modified such that it undergoes novel types of reactions. Sulfenes R 1 R 2 CϭSO 2 are short-lived intermediates that may be generated for example by 1,2-elimination or [2 ϩ 4]-cycloreversion reactions. [2] Their typical transformations include 1,2-additions across the CϭS double bond, nucleophilic addition at sulfur, and cycloadditions.