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Tip of the Month

This is one of our best "automatic PTC triggers." If you are using DMSO, DMF, NMP or DMAC for nucleophilic substitutions, there is a very high probability that you can replace these solvents with phase-transfer catalysis and water-immiscible solvents (or no solvent!) to greatly improve workup which will result in higher isolated yield, less waste and much better solvent recovery. There is no doubt that these high boiling polar aprotic solvents provide excellent reactivity in nucleophilic substitutions, however, they are usually hard to recover, keep dry and avoid entraining product during workup. Wouldn't you much rather use PTC and toluene (for example), separate the phases at the end of the reaction and proceed with easy workup, product isolation and solvent recovery?*

Contact Marc Halpern at tel (+1) 856-222-1146 or by E-mail [1] if you would like us to send you a table comparing DMSO to PTC/toluene, or [2] if you have a potential opportunity to replace DMSO, DMF, NMP or DMAC with PTC, or [3] if you disagree with the statement that PTC can usually advantageously replace these solvents.

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PTC 2-Day Course Deadline extended to April 7 

Last chance to register for the 2-day course "Practical Phase-Transfer Catalysis" to be held in New Jersey on May 6-7, 2003. Click here for the agenda. Alternatively, train your whole department on-site, in a private in-house course. Since 1996, 480 process development chemists, synthesis chemists and process engineers from 87 companies have greatly benefited from 28 public and private in-house PTC courses in the US and Europe. This is the only public PTC course in the US in 2003 (Japan planned for October 2003). A veteran pharmaceutical process chemist wrote (Apr 2002 course): "Best training in my 18 years in industry." He also reported scaling up a new PTC process within 6 months.  Registration Deadline: April 7, 2003.

PTC Reaction of the Month

Here is a report of a very challenging nucleophilic substitution in which DMSO doesn't work and PTC gives 98% isolated yield. To quote from the article: "Several attempts to make an alpha-azido ester by reaction of an alpha-chloro boronic ester with an alkali metal azide in DMSO have been unsuccessful." Eventually, the authors achieved the results shown below by using PTC and restricting the temperature with a very long reaction time. The authors note very importantly that using azide with dichloromethane can form an extremely explosive byproduct and hence they use other solvents.* Singh, R.; Matteson, D.; J. Org. Chem., 2000, 65, 6650.

PTC Breakthrough Process Screening

PTC Organics offers PTC Breakthrough Process Screening for rapid and highly effective evaluation of breakthrough phase-transfer catalysis processes. As the world leader in industrial phase-transfer catalysis, PTC Organics develops breakthrough high-performance low-cost PTC processes. Contact Marc Halpern at PTC Organics by E-mail, website, telephone (+1 856-222-1146) or fax (+1 856-222-1124).

Meet PTC Organics at Chemspec  

Learn how PTC Organics can help you improve process performance and process R&D effectiveness using Phase-Transfer Catalysis by scheduling a meeting with Marc Halpern at Chemspec  to be held in Manchester, UK on June 4-5, 2003. The meetings will be held in the SOCMA lounge area (PTC Organics is a SOCMA member).
Contact Marc Halpern at PTC Organics by E-mail, website, telephone (+1 856-222-1146) or fax (+1 856-222-1124).


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* Before 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 E-mail 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 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 #7
Copyright 2003 PTC Communications, Inc.