Two Carbonylations of Methyl Iodide and Trimethylamine to Acetic acid and N,N-Dimethylacetamide by Rhodium(I) Complex: Stability of Rhodium(I) Complex under Anhydrous Condition

Catalysts

Jang-Hwan Hong¹ 

[1] Department of Nanopolymer Material Engineering, Pai Chai University, 155-40 Baejae-ro (Doma-Dong), Seo-Gu, Daejon 302-735, Korea; E-Mail

关键词: rhodium;    carbonylation;    trimethylamine;    dimethylacetamide;    methyl iodide;    acetic acid;    tetramethylammonium iodide;    intramolecular;    inner-sphere;   

DOI  :  10.3390/catal5041969

来源: mdpi

【 摘 要 】

Rhodium(I)-complex [Rh(CO)₂I₂⁻] (1) catalyzed two carbonylations of methyl iodide and trimethylamine in NMP (1-methyl-2-pyrolidone) to acetic acid and DMAC (N,N-dimethylacetamide) in the presence of calcium oxide and water. The carbonylation of trimethylamine continued during the carbonylation and consumption of methyl iodide. In total, 183.8 mmol of carbonylated products was produced while consuming 24.1 mmol methyl iodide via acetic acid formation. These results clearly indicated that there were two carbonylation routes of trimethylamine and methyl iodide and the carbonylation rate of trimethylamine was faster than that of methyl iodide. Rhodium(I)-complex [Rh(CO)₂I₂]⁻ (1) in the presence of trimethylamine was stable enough to be used  25 times with TON (Turnover Number) of 368 for DMAC and TON of 728 for trimethylamine. Inner-sphere reductive elimination in stepwise procedure was suggested for the formation of DMAC instead of acyl iodide intermediate under anhydrous condition.

【 授权许可】

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