单模聚焦微波合成N-烷基-N-羧甲基咪唑类酸性离子液体

Synthesis of N-alkyl-N-carboxymethyl imidazolium acidic ionic liquid under microwave irradiation

以N-甲基咪唑、1-乙基咪唑、1-丙基咪唑为原料,采用单模聚焦微波辐射一锅两步法有效地合成了化合物1-甲基-3-羧甲基咪唑四氟硼酸离子液体(1)、1-乙基-3-羧甲基咪唑四氟硼酸离子液体(2)、1-丙基-3-羧甲基咪唑四氟硼酸离子液体(3).通过单因素实验,确定了最佳合成条件:化合物1在90 W,20 min,80℃条件下,产率达到88%;化合物2在110 W,30min,85℃条件下,产率达到89.2%;化合物3在110 W,30 min,80℃条件下,产率达到89.5%.用红外光谱和氢核磁共振表征3种离子液体的化学结构.首次通过浊点法检测了3种酸性离子液体与常见的无机盐溶液是否能够形成双水相体系.

A simple and efficient one-pot two-step procedure for the synthesis of product 1：1-methyl-3-carboxymethyimidazolium tetrafluoroborate,2：1-ethyl-3-carboxymethyimidazolium tetrafluoroborate,3：1-propyl-3-carboxymethyimidazolium tetrafluoroborate three ionic liquids based on N-methyimidazole,1-ethylimidazole,1-propylimidazole under the single-mode focused microwave-assisted condicions has been described.We identified the best synthetic conditions through single factor experiment,which were：1：90 W,20 min,80℃,with the yield 88%;2：110 W,30 min,85℃,with the yield 89.2%;3：110 W,30 min,80℃,with the yield 89.5%,respectively.These synthetic products were characterized by FT-IR spectrum and 1 H NMR.At the same time,this paper also explored that whether aqueous two-phase systems could form by acidic ionic liquids and common inorganic salt solution through cloud point method for the first time.