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QD Information Services now offers custom experimental designs. No matter what your need, QDIS can develop an experimental design to suit your needs. These designs are computer generated and are setup in order to give you the greatest confidence in the results results. DOE gives you the ability to know for sure if you are it the optimal settings for your process.

What is Design of Experiments (DOE)?

Design of Experiments is the use of a carefully selected group of experiments chosen to give the most information with the fewest number of experiments. While not well know, the technique has been around for many years. It is just now becoming popular as is a great tool for optimizing any process. If you need to maximize or minimize some measurement then DOE can help you. Not only do you get the most information from the fewest experiments, but you also generate a model which allows you to predict results at other areas within your experimental space.

What Can Design of Experiments Do for You?

• Optimize any process
• Optimize the yield of a chemical reaction
• Minimize the amount of an impurity
• Allows you to show that you understand and have a chemical process in control
• Gives you an indication of what further experiments may be needed

Contact QD Information Services for a free quote for an experimental design for your specific needs. Since each situation is unique, the pricing depends on your exact needs.

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Email Ed Vawter

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I want to talk about a couple of alternative solvents that get overlooked quite a bit in organic synthesis. The first is diethoxymethane (DEM; CAS [462-95-3]).

It has several uses based on it’s properties. First, it is a very good solvent fr Grignards and other organometallic reactions due to its low water levels typically less than 150 ppm (water solubility in DEM is 1.3% w/w). It llso has limited solubility in water; 4.2% w/w. It also has a low boiling ponit (88 °C) and Another attractive property is that DEM azetropes with ethanol (bp 74 °C, 58% DEM) and with water (bp 75 °C, 90% DEM).

It does tend to form peroxides after being opened and it is flammable (flashpoint of -5 °C). It is stable to base but does decompose under strong acid conditions.

While the solvent has been known for some time, it has only in the past ~6 years been commercially available in large quantities (55 gal drum to railroad tankcars from Eastman). It is in general a good replacement for dichloromethane, tetrahydrofuran, glyme (1,2-dimethoxyethane), and methylal (1,1-dimethoxymethane).

Here’s some information from Eastman Chemical and a publication from a few years ago in Org. Process Res. and Dev. 2001, 5, 127.

Eastman Chemical Information

Applications of Diethoxymethane as a Versatile Process Solvent and Unique Reagent in Organic Synthesis

Another solvent that gets overlooked is 1,3-dimethyl-2-imidazolidone (DMEU or DMI; CAS [80-73-9]). This can be used as a replacement for the highly toxic HMPA as a dipolar aprotic solvent.

It is very similar to 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone [7226-23-5] but has a lower boiling point.

It is similar to dimthylformamide but tends to be more stable. It is stable to alkali metals and strong bases and has a boiling point of 225 °C. Mitsui Chemicals America has a nice site with information on 1,3-dimethyl-2-imidazolidone including physical properties, chemical properties and some applications.

I have used both of these in my past and have been happy with the results and hope others will consider them for future projects.

Technorati Tags: process development, solvents

Email Ed Vawter

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