ISSN:
1434-1948
Keywords:
Enolates
;
Nucleophilic additions
;
Ruthenium
;
S ligands
;
Sulfenes
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Sulfene complexes [CpRu(PR′3)2(RHC=SO2)]PF6 (2a-d) are obtained from the corresponding sulfur dioxide complexes 1a-c and diazomethane or -ethane. Reaction of [CpRu(dppm)(SO2)]Cl (1d) and phenyldiazomethane gives the chlorobenzylsulfinato complex [CpRu(dppm)(SO2CHPhCl)] (3). Alternatively, 2a may be synthesized by sulfur dioxide addition to the carbene complex [CpRu(dppm)(CH2)]PF6 (5) which, in turn, is obtained from the corresponding methyl complex [CpRu(dppm)(CH3)] and [Ph3C]PF6. Treatment of 2a-d or 3 with the enolates of cyclic 2-methyl-1,3-diketones, methyl malonates, open-chain cyano or β-oxo esters, and cyclic β-oxo esters gives the C-C coupling products 6a, b, 7a-e, 8a-c, 9a-c in high yields and, in one case, with high diastereoselectivity as well. The functionalized sulfinate ligands thus formed may be alkylated and subsequently removed from the metal center by ligand substitution with acetonitrile. After MeCN/SO2 exchange, the ruthenium complex can be recycled.
Type of Medium:
Electronic Resource
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