Process for preparing cyanoacetates
This invention relates to a process for producing cyanoacetates using a cyanoacetamide as a precursor.
1. A process for the preparation of a cyanoacetate, steps of which comprise:
(a) contacting cyanoacetamide with an alcohol, in the presence of a mineral acid, under appropriate conditions and for a time sufficient to yield a cyanoacetate; and
(b) optionally, separating therefrom the so formed cyanoacetate, wherein the cyanoacetate is a C 1-20 alkyl cyanoacetate, a C 6-20 aryl cyanoacetate, a C 7-20 alkaryl cyanoacetate or a C 7-20 aralkyl cyanoacetate, any of which may be substituted by one or more hydroxyl groups or C 1-20 alkyl ether groups.
2. The process of claim 1 , wherein the cyanoacetate is a C 1-20 alkyl cyanoacetate selected from methyl cyanoacetate, ethyl cyanoacetate, propyl cyanoacetates, butyl cyanoacetates, pentyl cyanoacetates, octyl cyanoacetates, alkoxy ether alkyl cyanoacetates, allyl cyanoacetate, and combinations thereof.
3. The process of claim 1 , wherein the cyanoacetate is a C 6-20 aryl cyanoacetate.
4. The process of claim 1 , wherein the cyanoacetate is a C 7-20 aralkyl cyanoacetate.
5. The process of claim 1 , wherein the alcohol is an alkyl alcohol, an aryl alcohol, an alkaryl alcohol or an aralkyl alcohol.
6. The process of claim 1 , wherein the alcohol is selected from methanol, ethanol, propanols, proparganols, butanols, pentanols, hexanols, octanols, nonanols, oxononanols, decanols, dodecanols, allanol, cyclohexanol, tetrahydrofurfurol, chloroethanol, 2,2,2-trifluoroethanol, hexafluoroisopropanol, alkoxy ether alkanols, dialkyl siloxanols, or trialkylsilylalkanols.
7. The process of claim 1 , wherein the alcohol is an aromatic alcohol.
8. The process of claim 1 , wherein the alcohol is selected from phenol, benzyl alcohol or derivatives thereof.
9. The process of claim 1 , wherein the mineral acid is sulfuric acid, sulfurous acid, sulfonic acid, phosphoric acid, phosphorous acid, phosphonic acid, hydrochloric acid or hydrobromic acid.
10. The process of claim 1 , wherein the alcohol is used in excess to either or both of the cyanoacetamide and the mineral acid.
11. The process of claim 1 , wherein the cyanoacetate is formed in an amount of about 90% or greater.
12. The process of claim 1 , wherein step (b) is free from the cyanoacetamide, mineral acid, and/or alcohol, and by-products.
13. The process of claim 1 , wherein the cyanoacetate is phenyl cyanoacetate.
14. The process of claim 1 , wherein the cyanoacetate is selected from phenethyl cyanoacetate, benzyl cyanoacetate, or toluyl cyanoacetate.
15. The process of claim 1 , wherein the alcohol is present in an amount of from 2.5 equivalents to 10 equivalents, per equivalent of cyanoacetamide; and wherein the mineral acid is present in an amount of from 0.6 equivalents to 1.2 equivalents per equivalent of cyanoacetamide; wherein the cyanoacetate is formed in an amount of about 70% or greater.