Phase-transfer catalysis excels in etherification and in the vast majority of cases there is no better process technology for Williamson ether synthesis than PTC.
In this etherifcation, nearly quantitative yield was achieved with only 0.2 mole% excess of t-butyl bromo acetate. This illustrates PTC’s outstanding ability to achieve high atomic efficiency for both green chemistry as well as cost savings due to low excess of reactants. The strength of PTC is further demonstrated by the fact that the impressive results were achieved in an hour near room temperature.
Further cost reduction could be achieved by making adjustments to the phase-transfer catalyst. Since the leaving group in this reaction is bromide, then there is 10X more bromide than phase-transfer catalyst. That means that the hydrogen sulfate anion will be swamped out by bromide so there is no reason to use the expensive tetrabutyl ammonnium hydrogen sulfate when one could use the less expensive tetrabutyl ammonium bromide (TBAB). If this reaction were to be scaled up, we would recommend using TBAB and also reducing the catalyst loading to well under 10 mole%.
If your company can potentially benefit from achieving the lowest-cost highest-performance green chemistry using phase-transfer catalysis, now contact Marc Halpern of PTC Organics to explore how we can apply the most highly specialized expertise in industrial PTC to help your company improve profit, process performance and R&D efficiency.
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!).
