I was told that the ethyl ester of L-proline may not be synthesized from L-proline and ethyl alcohol in refluxing toluene, with an acid catalyst such as p-toluensulfonic acid for example, because toluene and ethanol and in this case water as well form an azeotrope. Is this true?
I do not have a supply of pure thionyl chloride, and that's why I am trying to use this route. I appreciate if anyone may answer this question.