soma
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synthesis of NAC methyl ester
In the patent ( http://www.sumobrain.com/patents/wipo/Method-preparation-n-a... ) (found by bereal511 -- thanks) they use dry methanol in the esterification of
n-acetylcysteine.
I'm wondering why since water is produced in the synthesis. Also, I'm thinking of synthesizing NAC ethyl ester which would be a little more difficult
to dry.
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Metacelsus
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They use it because water is produced in the synthesis. It's an equilibrium reaction, so if the methanol had water in it to start, the
conversion would be low.
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soma
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Thanks.
So then you could increase the yields by eliminating the water created by the reaction.
I'm wondering if maybe adding molecular sieve to the reaction mix would work.
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soma
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They also run this reaction for a really long time (22 hours). The esterifications I've looked at go for maybe 1 hour.
Would this be because they're running it at room temperature? And are they using low temps to prevent dimerization?
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