of the Month - Crucial
Practical Difference Between "Phase-Transfer Catalyst" and "Cationic Surfactant"
A common misperception is that a quaternary ammonium "phase-transfer catalyst" and "cationic surfactant" are the same thing. After all, "isn't a quat, a quat"? It is true that most cationic surfactants are quaternary ammonium salts and many phase-transfer catalysts also also quaternary ammonium salts. However, there is an extremely important distinction which we use in the design of practical applications (and sometimes for patent purposes). If one uses a typical cationic surfactant such as cetyl trimethyl ammonium bromide to enhance a reactant rate, emulsions are often formed which can sometimes make workup and isolation of product so difficult as to be impractical. In contrast, a good phase-transfer catalyst will not only enhance the reaction rate, but a well chosen phase-transfer catalyst will allow for phase separation within a minute or so after stopping agitation. Good phase separation allows easy product isolation and separation between product and waste. This is a major practical advantage which can be the difference between a feasible and non-feasible PTC application on any scale in the lab or plant. If you would like to discuss which structures are more likely to create emulsions and which structures are more likely to provide good catalyst separation, please contact Marc Halpern at tel +1 856-222-1146 or by E-mail.
Please forward this PTC Tip of the Month to your colleagues and encourage them to subscribe
Consulting - Stop Wasting
Precious R&D Resources & Improve Performance
What if you could achieve PTC breakthrough processes in your lab in weeks instead of months (if at all)? PTC Organics' dedicated industrial phase-transfer catalysis experts have provided highly specialized PTC consulting and other PTC services at 189 sites in the US, Europe and Japan and have helped companies save > $150 million and improve overall R&D effectiveness.
To improve route selection, process improvement, process development and overall reaction performance, contact Marc Halpern at tel +1 856-222-1146 or by E-mail.
Training - Plan
your training budget - November
2004 and May 2005 in Chicago and Newark
The course "Practical Phase-Transfer Catalysis" will be conducted in Chicago and Newark later in 2004 and 2005. You will have the option of attending both days of the course or choose only the "PTC Reactions" portion (e.g., for synthesis chemists) or the "PTC Process Development" portion (for process chemists/engineers). Starting in September, you will be able to purchase just the manual (without taking the course) or the manual with a transcript of the course. "Practical Phase-Transfer Catalysis" can also be conducted at your company anytime (North America, Europe or Japan) as a private in-house course. More than 530 chemists, engineers and managers at nearly 100 companies have participated in this highly rated course since 1996. Click here for details and agenda or contact us by E-mail or telephone (+1 856-222-1146) or fax (+1 856-222-1124).
Inexpensive patent attorney (United States) familiar with Phase-Transfer Catalysis, organic chemistry and biochemistry. Contact Mannie Morgenstern by E-mail or at telephone 818-788-5531 (California).
Reaction of the Month - Oxidation
of Sulfide to Sulfone
Chemists as Sumika Fine Chemicals performed a mild high yield oxidation of a thioether to the sulfone using hydrogen peroxide and catalyzed by 1 mole% each of TBAB, phenyl phosphonic acid and sodium tungstate. Shintaku, T.; Katsura, T.; Itaya, N. (Sumika Fine Chemicals) US Patent 6,740,770 25-May-2004
Catalyst of the Month - Tetraethylene
Glycol Dimethyl Ether "Tetraglyme"
When glymes work in PTC reactions, they are low cost alternative to using crown ethers; an excellent brochure comparing glymes to quats for a variety of PTC reactions is available from Clariant.
Glymes do not always work for PTC reactions; specific guidelines do not yet exist for choosing glymes as phase-transfer catalysts, so "trial-and-error" is the recommended method for screening
Availability, Samples and Quotes from Competitors
Request samples and quotes from: Clariant (click on link) - contact Dan Patterson (US)
Other Phase-Transfer Catalysts:
PTC Supplier Directory: choose from a dozen suppliers & 80 PT catalysts and ask for free samples & quotes.
Technology for Licensing
For details, contact Marc Halpern at tel +1 856-222-1146 or by E-mail.
Pharma - for PTC options during route selection, contact Marc Halpern by E-mail, website or telephone (+1 856-222-1146).
To stop receiving the "PTC Tip of the Month," contact us by E-mail at firstname.lastname@example.org or by telephone at +1 856-222-1146.
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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 #21 - June 2004
Copyright 2004 PTC Communications, Inc.
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