A patent that was issued this month provides us with a valuable learning opportunity. The inventors used 300 mole% of the expensive and hard-to-obtain tetrabutylammonium permanganate to perform an oxidation of an alcohol to a carboxylic acid.
In our 2-day course “Industrial Phase-Transfer Catalysis”, we teach on our famous page 76 in the course manual (same page for 20 years) the relative affinities of many anions towards quat cations. One of the anions with the highest affinity for quat cations is permanganate. The practical ramification of the very high affinity of permanganate to a quat cation relative to bromide, chloride or hydrogen sulfate is that we can avoid wasting a lot of money and forcing a huge amount of quat recycle or treatment if we use a catalytic amount of inexpensive tetrabutylammonium bromide with potassium permanganate in a molar amount required to perform the oxidation. In this case, we could reduce quat usage by 95%-99%!!
In addition, we should be able to replace the disadvantageous solvent that the inventors chose to be pyridine. The physical reaction matrix would be a solid-liquid PTC system and we would have the flexibility to choose from a wide variety of convenient, inexpensive and easily recyclable solvents (not to mention avoiding the terrible stench of pyridine).
In summary, if this reaction had to be scaled up, we should be able to reduce the quat salt cost by 99% due to 95%-99% lower usage and the much lower cost of TBAB versus TBAMnO4. We should also be able to replace the solvent with a more advantageous solvent.
Now contact Marc Halpern of PTC Organics when you need to streamline your processes and achieve low-cost high-performance green chemistry by using our highly specialized expertise in industrial phase-transfer catalysis.
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!).
