Benzyl trimethyl ammonium chloride (BTMAC) is one of the least expensive phase-transfer catalysts since it is made from commodity benzyl chloride and commodity trimethyl amine. Moreover, the process for making BTMAC is simply reacting an aqueous solution of trimethyl amine with benzyl chloride and stripping some water until it is 60% BTMAC and shipping everything in the reactor.
BTMAC almost never gives the highest reactivity in PTC systems since it has only 10 carbon atoms (C# is not high enough) and the accessibility of the positive charge on the nitrogen (q-value = 3.14) is so high that it makes tighter ion pairs more than almost any other quaternary ammonium phase-transfer catalyst. Nevertheless, BTMAC is used is some commodity polymer PTC reactions, because its low price combined with the rate enhancement it provides relative to not using PTC is simply worth the investment. BTMAC is toxic and must be handled with care.
Benzyl Trimethyl Ammonium Chloride is available from Dishman and Biosolutions
Need to learn more about which phase-transfer catalyst to choose for a specific PTC application? Contact Marc Halpern of PTC Organics by E-mail.
Directory for suppliers of 80 PTC’s
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!).
