Back to Search
Start Over
Dioxomolybdenum(VI) complexes as catalysts for the hydrosilylation of aldehydes and ketones.
- Source :
-
Dalton transactions (Cambridge, England : 2003) [Dalton Trans] 2006 Apr 21 (15), pp. 1842-6. Date of Electronic Publication: 2006 Feb 23. - Publication Year :
- 2006
-
Abstract
- The dioxomolybdenum(VI) complexes [MoO2Cl2] (1), [MoO2(acac)2] (2), [MoO2(S2CNEt2)2] (3), [CpMoO2Cl] (4), [MoO2(mes)2] (5) and the polymeric organotin-oxomolybdates [(R3Sn)2MoO4] [R = n-Bu (6), t-Bu (7), Me (8)] were examined as catalysts for the hydrosilylation of aldehydes and ketones with dimethylphenylsilane. Of these, [MoO2Cl2] (1) was the most efficient catalyst, affording quantitative yields of the corresponding silylated ethers at room temperature in acetonitrile. Complexes 2, 4-8 also catalyzed the same reaction but required heating at 80 degrees C and longer reaction times compared with 1. Compound 3 is inactive. The wide scope of molybdenum oxide-mediated hydrosilylation was established with a variety of aldehydes and ketones. Counter intuitively, the activity of is 1 highest in NCMe. In the absence of a carbonyl substrate, [MoO2Cl2(NCBu(t))] (10) reacts with HSiMe2Ph affording [MoO(OSiMe2Ph)Cl2]2 (11) which has been fully characterized by NMR and IR spectroscopy, elemental analyses and mass spectrometry. Addition of radical scavengers strongly slows down the [MoO2Cl2]-based hydrosilylation suggesting the intermediacy of oxygen-centered radicals.
Details
- Language :
- English
- ISSN :
- 1477-9226
- Issue :
- 15
- Database :
- MEDLINE
- Journal :
- Dalton transactions (Cambridge, England : 2003)
- Publication Type :
- Academic Journal
- Accession number :
- 16585971
- Full Text :
- https://doi.org/10.1039/b514930d