Abstract
The reactions of Ru3(CO)9(μ3-η2-CH 3C=NCH2CH3)(μ-H) (1), M3(CO)9(μ3-η2-C=N(CH 2)3)(μ-H) (M = Ru (2), M = Os (3)) with the alkynes RC≡CR (R = CH3, C6H5, CO2Me) have been studied. The ruthenium complexes 1 and 2 react with 2-butyne at 70 °C to give two very different trimetallic alkyne derivatives: Ru3(CO)7(μ-η2:η4-C 4(CH3)4)(μ-η2-CH 3C=NCH2CH3)-(η1-COC(CH 3)C(H)CH3 (5) and Ru3(CO)8(μ3-η2-C=N(CH 2)3)(μ-η2-CH3C(H)=CCH 3) (6). The osmium imidoyl 3 does not react with 2-butyne even at elevated temperatures. However, the reaction of Os3(CO)9(μ-η2-C=N(CH2) 3)(μ-H)(CH3CN) (7b), synthesized from Os3(CO)10-(μ-η2-C=N(CH2) 3)(μ-H) (7a), with 2-butyne yields the analog of 6, Os3(CO)8(μ3-η2-C=N(CH 2)3)(μ-η2-RC(H)=CR) (R = CH3 (10), R = C6H5 (11)) on thermolysis of the initially formed nonacarbonyl precursors (8 and 9 for R = CH3), which are a mixture of isomers. Direct reaction of 7a with diphenylacetylene at 100 °C gives somewhat lower yields of 11. The reaction of 7b with dimethylacetylenedicarboxylate or the direct reaction of 3 with this alkyne yields the nonacarbonyl derivative Os3(CO)9(μ-η2-C=N(CH2) 3)(μ3-η3-CH3O 2CC=C(H)CO2CH3) (12). Direct reaction of 7a with a 2.5 molar excess trimethylamine N-oxide at room temperature yields the alkyne-imidoyl-coupled product Os3(CO)8(μ-η6-CH 3C(H)=C(CH3)C-(CH3)=C(CH 3)C=N(CH2)3) (13). The solid state structures of 5, 11, 12, and 13 are reported. A comparative study of the electrochemical properties of 5 and 1 is also reported.
Lingua originale | Inglese |
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pagine (da-a) | 2674-2681 |
Numero di pagine | 8 |
Rivista | Organometallics |
Volume | 16 |
Numero di pubblicazione | 12 |
DOI | |
Stato di pubblicazione | Pubblicato - 1 gen 1997 |
Pubblicato esternamente | Sì |