27000-70-0Relevant academic research and scientific papers
Carbon dioxide utilization in the efficient synthesis of carbamates by deep eutectic solvents (DES) as green and attractive solvent/catalyst systems
Dindarloo Inaloo, Iman,Majnooni, Sahar
, p. 11275 - 11281 (2019/07/31)
A green and eco-friendly solvent/catalyst system based on a deep eutectic solvent (DES) was devised and developed for the simple synthesis of carbamates through three-component coupling of amines, alkyl halides and carbon dioxide (CO2). It was found that choline chloride:zinc(ii) chloride ([ChCl][ZnCl2]2) was very proficient and effective for the activation and utilization of CO2 in carbamate formation reactions from a wide scope of amines. Surprisingly, this strategy provides the desired carbamates under atmospheric CO2 pressure at room temperature. In particular, both aromatic and aliphatic amines were effective and demonstrated excellent yields. Besides, the [ChCl][ZnCl2]2 exhibited very high stability and also could be reused for at least five consecutive cycles without any significant loss of activity. It is worth noting that this is the first solvent/catalyst system which can be recycled successfully from the reaction mixture.
Novel Synthesis of Carbamate Ester from Carbon Dioxide, Amines, and Alkyl Halides
Yoshida, Yasuhiko,Ishii, Shigeru,Watanabe, Masayo,Yamashita, Tadataka
, p. 1534 - 1538 (2007/10/02)
A novel synthesis of carbamate ester using carbon dioxide as a direct material is reported in this article.The direct reaction of carbon dioxide, aliphatic amines, and alkyl halides was found to give the corresponding alkyl carbamate esters in good yields.Reactions using secondary alkyl bromides gave carbamate esters in higher yields than those using primary or tertiary alkyl bromides.The carbamate ester yields increased with the addition of N,N-dimethylformamide to the reaction system of carbon dioxide, amines, and alkyl halides.This reaction is considered to prooced by an SN2 displacement reaction of the alkyl halide by the carbamate anion formed from the reaction of carbon dioxide and the amine.
