One of the most comprehensive screening of catalysts ever described in a PTC-related patent was reported in Falling, S. (Eastman Chemical) US Patent 6,395,912, 28-May-2002. This patent has 331 examples and most of them use quaternary phosphonium or ammonium iodides with organotin iodides or zinc iodide as Lewis acid catalyst, with no additional solvent, for the isomerization of epoxybutene to dihydrofuran which is an intermediate for the commodity chemical THF. When a lot of profit is at stake, it is worthwhile to invest R&D resources to screen a lot of catalysts.
This patent is an improvement over previous patents for producing DHF by BASF such as US Patent 5,627,291 and more importantly US 5,034,545. The latter used polyethylene glycols and crown ethers as the phase-transfer catalyst and was the subject of a lawsuit between BASF and Eastman (see http://www.ipmall.info/hosted_resources/Markman/pdfFiles/1998.03.24_BASF_CORPORATION_v._EASTMAN_CHEMICAL.pdf).
PTC Organics has highly specialized expertise in choosing phase-transfer catalysts based on nearly four decades of experience in using the fundamentals of PTC to choose the best catalyst, customized for each application.
PTC Organics also works with attorneys in patent cases such as the one cited above to understand the basis for disputes relating to patent claims involving phase-transfer catalysis.
Now contact Marc Halpern of PTC Organics to learn how PTC Organics can help your company improve process performance, protect PTC-related intellectual property and increase profit using 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!).
