795306-52-4Relevant academic research and scientific papers
Observations on reaction pathways of dicobalt octacarbonyl with alkynyl amines
Hong, Fung-E.,Huang, Yi-Luen,Chen, Hsueh-Liang
, p. 3449 - 3460 (2007/10/03)
Treatments of a bis(diphenylphosphino)methylene (dppm) bridged dicobalt complex, Co2(CO)6(dppm) (4), with propargylamine and 4-ethynylaniline at 25 °C for 24 h gave [(dppm)Co2 (CO)4(μ-HC≡CCH2NH2)] (5) and [(dppm)Co2(CO)4(μ-HC≡CC6 H4NH2)] (6), respectively. Interestingly, only alkynyl amines bridged dicobalt complexes were obtained rather than the previously observed coupling products. The results are in acceptance with the proposed mechanism which describes the formation of the coupling products {[Co2(CO)6(μ-HC≡C-)] -CH2NH}2C=O (1) and {[Co2(CO) 6(7μ-HC≡C-)]-C6H4N}2 (2) from the reaction of Co2(CO)8 with propargylamine and 4-ethynylaniline, respectively. Similar results were attained for the reactions of 4 with propioamide and 1-ethynylcyclohexylamine at 25 °C for 24 h which yielded [(dppm) Co2(CO)4(μ-HC≡CC(=O)NH2)] (7) and [(dppm)Co2(CO)4(μ-HC≡CC6 H10NH2)] (8), respectively. Reaction of 1-ethynylcyclohexylamine with one molar equivalent of Co2(CO)8 in THF at 25 °C for 15 min gave an alkyne bridged dicobalt complex, [Co2(CO)6 (μ-HC≡ CC6H10NH2)] (9). Direct treatment of 3-ethynlaniline with one molar equivalent of Co2(CO)8 in THF at 25 °C for 1 h gave an alkyne bridged dicobalt complex, [Co2(CO)6 (μ-HC≡CC6 H4NH2)] (11) and an azobenzene derivative, {[Co2(CO)6 (μ-HC≡C)]C6H4N}2 (10). Further treatments of 8, 9, and 11 with one molar equivalent of Sanger's reagent, 2,4-dinitrofluorobenzene, in THF at25 °C for 48 h gave [(dppm)Co2(CO)4 (μ-HC≡CC6H10NHC6H3 (NO2)2)] (13), [Co2(CO)6 (μ-HC≡CC6H10NHC6H3 (NO2)2)] (14), and [Co2(CO)6 (μ-HC≡CC6H4NHC6H3 (NO2)2)] (15), respectively.
