Preparation of Ruthenium Azirinyl Complexes and Reversed Regiospecificity of the Carbonyl Insertion Reaction
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- 作者：Yih-Hsing Lo ; Sheng-Cheng Hsu ; Shou-Ling Huang ; Ying-Chih Lin ; Yi-Hong Liu ; and Yu Wang
- 刊名：Organometallics
- 出版年：2004
- 出版时间：December 6, 2004
- 年：2004
- 卷：23
- 期：25
- 页码：5924 - 5933
- 全文大小：198K
- 年卷期：v.23,no.25(December 6, 2004)
- ISSN：1520-6041
文摘
Electrophilic addition of organic halides to [Ru]CN (1; [Ru] = Cp(PPh3)2Ru) gave thecationic isocyanide complexes {[Ru]CNCH2R}X (R = CN, 2a; R = CH=CH2, 2b; R = Ph,2c), which reacted with base (n-Bu4NOH or n-Bu4NF) to give the three-membered-ringazirinyl complexes. For the azirinyl complex with a phenyl group 3c, three isomers, assignedas ruthenium 2H- and 1H-azirinyl complexes, are observed at -20 
C. Reaction of the methylisocyanoacetate complex {[Ru]C
NCH2COOMe}X (2d) with n-Bu4NOH causes hydrolysisof the ester group to give the ruthenium oxazolone complex 4d. The insertion of the C=Ogroup of acetone, aldehyde, ester, and amide into the C-C bond of the three-memberedazirinyl ring of 3a-c yields a variety of five-membered oxazolinyl complexes 5-7. Theregiospecificity of the insertion differs from that observed in the photochemically inducedcarbonyl insertion in the organic azirine system. The diastereoselectivity in the formationof 5-7 is controlled by steric effects. In the formation of the pentamethylcyclopentadienyloxazolinyl ruthenium complex 7a*, the intermediate 8a* is isolated before cyclization.Molecular structures of 7a* and 8a* have been determined by single-crystal X-ray diffractionanalysis. Treatment of 7 with hydride gave [Ru]CN and alcohol.
C. Reaction of the methylisocyanoacetate complex {[Ru]CNCH2COOMe}X (2d) with n-Bu4NOH causes hydrolysisof the ester group to give the ruthenium oxazolone complex 4d. The insertion of the C=Ogroup of acetone, aldehyde, ester, and amide into the C-C bond of the three-memberedazirinyl ring of 3a-c yields a variety of five-membered oxazolinyl complexes 5-7. Theregiospecificity of the insertion differs from that observed in the photochemically inducedcarbonyl insertion in the organic azirine system. The diastereoselectivity in the formationof 5-7 is controlled by steric effects. In the formation of the pentamethylcyclopentadienyloxazolinyl ruthenium complex 7a*, the intermediate 8a* is isolated before cyclization.Molecular structures of 7a* and 8a* have been determined by single-crystal X-ray diffractionanalysis. Treatment of 7 with hydride gave [Ru]CN and alcohol.