Process for preparing electron deficient olefin precursors
This invention relates to a process for producing electron deficient olefin precursors, such as 2-cyanoacetates, using an acid catalyzed transesterification reaction.
1. A process for the preparation of a cyanoacetate, steps of which comprise:
(a) reacting an ester of cyanoacetic acid and an alcohol, in the presence of a catalyst comprising a lanthanide element, wherein the lanthanide element comprises ytterbium, under appropriate conditions and for a time sufficient to yield a cyanoacetate;
wherein the alcohol is present in an amount of from about 0.5 to about 2.0 equivalents relative to the ester of the cyanoacetic acid; and wherein the catalyst is present in an amount of up to about 20 mol %;
(b) optionally, separating the so-formed cyanoacetate from the reaction mixture to be substantially free from the ester of cyanoacetic acid the alcohol and/or the catalyst, and by-products.
2. The process of claim 1 , wherein the catalyst comprising a lanthanide element has one or more ligands bound to the element(s).
3. The process of claim 2 , wherein the one or more ligands is selected from halogens, triflates, mesylates, nitrates or tosylates.
4. The process of claim 1 , wherein the alcohol is any mono-, di- or multi-functional hydroxyl compound.
5. The process of claim 1 , wherein the alcohol is any mono-, di- or multi-functional C 1-20 alkanol, C 2-20 alkenol, or C 2-20 alkynol.
6. The process of claim 1 , wherein the alcohol is an aromatic alcohol.
7. The process of claim 1 , wherein the alcohol is phenol, benzyl alcohol or derivatives thereof.