Coupling reaction of vinyl esters with aldehydes catalyzed by samarium complexes
- Kansai Univ. Suita, Osaka (Japan)
In recent years, a unique catalysis of samarium(II) complexes such as Cp*{sub 2}Sm(thf){sub 2} is increasing interest in organic synthesis. The authors now find that Sm(II) complexes catalyze a new 1:2 coupling reaction of vinyl esters and aldehydes under mild conditions. For instance, the coupling reaction of vinyl acetate with acetaldehyde under the influence of Cp*{sub 2}Sm(thf){sub 2}(10 mol%) in toluene at room temperature for 3 h afforded a 1:2 coupling product 3a, in 80% yield. From the examination of the reaction of 1a with cyaclohexanecarbaldehyde using several samarium complexes as catalysts, Cp*{sub 2}Sm(thf){sub 2} was found to be the best catalyst. In the coupling of 1a with benzaldehyde, however, SmI{sub 2} was more efficient than CP*{sub 2}Sm(thf){sub 2} to form the corresponding coupling product in almost quantitative yield (>99 %). The reaction of isopropenyl acetate with deutrated acetaldehyde, CD{sub 3}CDO, afforded a coupling product, 5, in which 11 deuteriums are incorporated in the molecule. The authors will present a detailed reaction mechanism in the Cp*{sub 2}Sm(thf){sub 2} - catalyzed coupling reaction of vinyl acetates with aldehydes.
- OSTI ID:
- 250087
- Report Number(s):
- CONF-9508100-; TRN: 96:002623-0025
- Resource Relation:
- Conference: 8. IUPAC symposium on organometallic chemistry directed towards organic synthesis, Santa Barbara, CA (United States), 6-10 Aug 1995; Other Information: PBD: 1995; Related Information: Is Part Of Eight IUPAC symposium on organometallic chemistry directed towards organic synthesis (OMCOS 8); PB: 375 p.
- Country of Publication:
- United States
- Language:
- English
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