PTC Tip of the Month, PTC Training PT Catalyst of the Month, PTC Reaction of the Month,
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9 metric tons of TBAC
A quantity of 9 MT of tetrabutyl ammonium chloride is available from Nagase. Send your inquiry by E-mail and use "TBAC 9MT" as the Subject Line.
of the Month - CPhI
News: Dramatic Price Reduction for Hydrogen Sulfate Quats
Discussions with phase-transfer catalyst suppliers at CPhI last week revealed that the price of hydrogen sulfate quats has dropped dramatically during the past year as the volumes of these quats has now surpassed several hundred tons per year. In fact, we heard of one price for tetrabutyl ammonium hydrogen sulfate (TBAHS) in large quantities which rivals the price of the corresponding bromide (TBAB) of 5 years ago. Since TBAHS almost always provides higher reactivity than TBAB and also often reduces byproducts and environmental issues related to bromide, we at PTC Organics intend to use TBAHS more often for commercial development as a result of this drop in price. Commercial suppliers of TBAHS are shown below in the PT Catalyst of the Month and we recommend contacting them directly for quotes.
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Top PTC Resources
The 2-day course "Practical Phase-Transfer Catalysis" will be conducted in three locations in 2004. Click here for agenda. For registration, contact us by E-mail, website, telephone (+1 856-222-1146) or fax (+1 856-222-1124).
February 2004 - Midland, Michigan
April 2004 - Tokyo, Japan
May 2004 - Mt. Laurel, New Jersey (near PTC Organics)
Anytime - private in-house course (optional Opportunity Identification Session under secrecy agreement)
Catalyst of the Month - Tetrabutyl
Ammonium Hydrogen Sulfate
Initial reaction rates are often much higher than for the corresponding bromide (TBAB) due to up to 1000 times less competition for extraction of the reacting anion. The absence of halides allows users to sometimes claim the use of a "greener" catalyst. Several reports of PTC oxidations using bleach or hydrogen peroxide have noted that the hydrogen sulfate provides higher yield than the corresponding bromide or chloride (note: highly detailed and diligent safety analysis must be performed before attempting any PTC oxidation). Can often be separated by extraction into water. Price has dropped dramatically recently as volume increased.
Stability is limited at high temperatures in the presence of strong base due primarily to Hofmann elimination. Price will probably always be higher than TBAB though much lower than just a few years ago.
Reactivity Parameters (Contact PTC Organics for explanation)
C# = 16; Accessibility q-value = 1.00. When using with base, make sure to take
into account the acidic proton of the HSO4 when determining how much base to
Availability, Samples and Quotes from Competitors
Request samples and quotes from: Cognis Corporation, Delta Finochem, Dishman Pharmaceuticals & Chemicals, GFS Chemicals, Lion Akzo, Nehachem, Rutherford Chemicals, SACHEM (click on link)
PTC Reaction of the Month - Selective
This October 2003 patented reaction was performed in a 100 L reactor. A major challenge was successfully overcome by using PTC, which was to avoid the formation of the difficult to remove N-alkylated contaminant, which also represents a significant yield loss (previous yields were 50-74%!). Aki, S.; Kurimura, M.; Nishi, T.; Minamikawa, J.; Tominaga, M.; Fukuyama, N.; Yamamoto, A. (Otsuka Pharmaceutical) US Patent 6,630,590 2003
Production Costs Too High?
Increase Yield: Could a 5-10% yield increase significantly increase profit (e.g., is your current yield < 88%)?
Reduce Cycle Time: Does your current process take > 8 hours? Want to eliminate isolation of intermediates?
Replace Strong Base with NaOH: Are you using alkoxides (e.g., methylate, t-butoxide), Na hydride, Na amide?
Improve Selectivity: Do you need to improve product assay or simplify workup? Too much hydrolysis?
Reduce Excess Reactants: Are you using > 10% excess of any expensive and/or hazardous reactant?
Replace Solvent for Easier Workup: Are you using DMSO, NMP, DMF, DMAC or undesirable solvent?
Increase Reactor Volume Efficiency: Does solvent and/or water take up > 50% of your reactor volume?
Other Challenges: Competing with China and India? Too much waste? Working with water-sensitive compounds?
If you answered "Yes" to even one question above and your reaction type is one of 35 on the PTC Reaction list, then Phase-Transfer Catalysis may help you achieve BREAKTHROUGH process improvement and improve profit margin and competitiveness.
INQUIRY: Contact Marc Halpern at PTC Organics by E-mail, website, telephone (+1 856-222-1146) or fax (+1 856-222-1124) to inquire about using PTC to improve process performance. As the world leader in industrial phase-transfer catalysis, PTC Organics offers PTC Breakthrough Process Screening for rapid and highly effective evaluation of breakthrough high-performance low-cost phase-transfer catalysis processes.
- Meet PTC Organics
Informex 2004 - January 19-22, 2004 in Las Vegas, Nevada, USA. PTC Organics booth # will be 2206.
2-Day PTC Course - public PTC courses are being planned for Michigan, New Jersey & Japan for the 1st half of 2004. For details Contact Us.
PTC Organics is a member of SOCMA
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performing any PTC reactions read this important message
Organic chemical reactions are inherently dangerous. Moreover, phase-transfer catalysis may provide rate and other enhancements which can intensify associated hazards. Under no circumstances should anyone perform any procedure on any scale based in whole or in part on any of the contents of this information provided here before thoroughly establishing safe operating procedures and performing a full and competent hazardous operations analysis with the participation of qualified technical personal trained in chemical, engineering, safety, industrial hygiene and environmental disciplines and sciences.
The list of PTC Tip of the Month subscribers will not be sold, rented or transferred and will be used only by PTC Communications, Inc. and PTC Organics, Inc. to provide information related to Phase-Transfer Catalysis. PTC Communications, Inc. reserves the right to distribute the PTC Tip of the Month to selected industrial chemists, engineers and managers.
PTC Tip of the Month #14 - November 2003
Copyright 2003 PTC Communications, Inc.
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