The ionic liquids, tetraethylammonium imidazolate, tetrabutylammonium imidazolate and decyl trimethyl ammonium imidazolate were prepared in high yield by a simple procedure that mixed the quat chloride with 1.0 equivalent of sodium imidazolate in water, stirred at r.t. for 2 hours, dried and treated with ethanol.
Following is the procedure described in Jung; I., Pyun; L., Min; B., Lee; J., Jeong; J. (SK Innovation Co.) US Patent Application Publication 2025/0153143, 15-May-2025
4.60 g (27.8 mmol) of tetraethylammonium chloride, 2.50 g (27.8 mmol) of sodium imidazolate, and 10 mL of distilled water were added to 100 mL of RBF, and the solution was stirred at room temperature for 2 hours and dried under vacuum at 50° C. for 5 hours. Next, 20 mL of ethanol was added thereto, the solution was stirred at room temperature for 2 hours to produce a white solid, which was then removed, and the filtrate was dried under vacuum at 50° C. for 15 hours to obtain 5.1 g (93%) of a highly viscous yellow liquid.
About Marc Halpern
Dr. Halpern is founder and president of PTC Organics, Inc., the only company dedicated exclusively to developing low-cost high-performance green chemistry processes for the manufacture of organic chemicals using Phase Transfer Catalysis. Dr. Halpern has innovated PTC breakthroughs for pharmaceuticals, agrochemicals, petrochemicals, monomers, polymers, flavors & fragrances, dyes & pigments and solvents. Dr. Halpern has provided PTC services on-site at more than 260 industrial process R&D departments in 37 countries and has helped chemical companies save > $200 million. Dr. Halpern co-authored five books including the best-selling “Phase-Transfer Catalysis: Fundamentals, Applications and Industrial Perspectives” and has presented the 2-day course “Practical Phase-Transfer Catalysis” at 50 locations in the US, Europe and Asia.
Dr. Halpern founded the journal “Industrial Phase-Transfer Catalysis” and “The PTC Tip of the Month” enjoyed by 2,100 qualified subscribers, now beyond 130 issues. In 2014, Dr. Halpern is celebrating his 30th year in the chemical industry, including serving as a process chemist at Dow Chemical, a supervisor of process chemistry at ICI, Director of R&D at Sybron Chemicals and founder and president of PTC Organics Inc. (15 years) and PTC Communications Inc. (20 years). Dr. Halpern also co-founded PTC Interface Inc. in 1989 and PTC Value Recovery Inc. in 1999. His academic breakthroughs include the PTC pKa Guidelines, the q-value for quat accessibility and he has achieved industrial PTC breakthroughs for a dozen strong base reactions as well as esterifications, transesterifications, epoxidations and chloromethylations plus contributed to more than 100 other industrial PTC process development projects.
Dr. Halpern has dedicated his adult life to his family and to phase-transfer catalysis (in that order!).
