Process for preparing electron deficient olefin precursors
View Patent ↗This invention relates to a process for producing electron deficient olefin precursors, such as 2-cyanoacetates, using an acid catalyzed esterification reaction.
1. A process for the preparation of a cyanoacetate, steps of which comprise:
(a) reacting cyanoacetic acid and an alcohol, in the presence of a catalyst comprising a lanthanide element or a transition element, under appropriate conditions and for a time sufficient to yield a cyanoacetate;
(b) optionally, separating therefrom the so formed cyanoacetate substantially free from the cyanoacetic acid, the alcohol, and/or catalyst, and by-products.
2. A process for the preparation of an electron deficient olefin precursor, steps of which comprise:
(a) reacting:
(i) a 2-electron withdrawing group-substituted methylene compound embraced by:
wherein EWG represents an electron withdrawing group selected from the group consisting of cyano or nitrile, alkoxy or aryloxy, carboxyl, sulphonic acids, carbonyls, halogens, nitro, isocyanate, sulfoxide and phosphine oxide; and R here represents hydrogen; and
(ii) an alcohol,
in the presence of a catalyst comprising a lanthanide element or a transition element, under appropriate conditions and for a time sufficient to yield an electron deficient olefin precursor embraced by:
wherein EWG represents an electron withdrawing group selected from the group consisting of cyano or nitrile, alkoxy or aryloxy, carboxyl, sulphonic acids, carbonyls, halogens, nitro, isocyanate, sulfoxide and phosphine oxide; and R here represents straight chain, branched, cyclic or fused C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, and C 6-20 aryl or C 7-20 alkaryl, with or without substitution or interruption by one or more heteroatoms; and
(c) optionally, separating therefrom the so formed electron deficient olefin precursor substantially free from the cyanoacetic acid, the alcohol, and/or catalyst, and by-products.
3. The process of claim 1 , wherein the catalyst comprising a lanthanide element or a transition element has one or more ligands bound to the element(s).
4. The process of claim 1 , wherein the catalyst comprises a lanthanide element.
5. The process of claim 1 , wherein the catalyst comprises a transition element.
6. The process of claim 1 , wherein the catalyst comprises ytterbium.
7. The process of claim 1 , wherein the catalyst comprises niobium, zirconium or scandium.
8. The process of claim 3 , wherein the one or more ligands is selected from halogens, triflates, mesylates, nitrates or tosylates.
9. The process of claim 1 , wherein the alcohol is any mono-, di- or multi-functional hydroxyl compound.
10. 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.
11. The process of claim 1 , wherein the alcohol is an aromatic alcohol.
12. The process of claim 1 , wherein the alcohol is phenol or benzyl alcohol.
13. The process of claim 2 , wherein the so-formed electron deficient olefin precursor is a cyanoacetate.
14. A process for the preparation of a cyanoacetate, steps of which comprise:
(a) reacting cyanoacetic acid and an alcohol, in the presence of a catalyst comprising a lanthanide element or a transition element, under appropriate conditions and for a time sufficient to yield a cyanoacetate;
(b) optionally, separating the so formed cyanoacetate substantially free from the cyanoacetic acid, the alcohol, and/or catalyst, and by-products.
15. The process of claim 2 , wherein the catalyst comprising a lanthanide element or a transition element has one or more ligands bound to the element(s).
16. The process of claim 2 , wherein the catalyst comprises a lanthanide element.
17. The process of claim 2 , wherein the catalyst comprises a transition element.
18. The process of claim 2 , wherein the catalyst comprises ytterbium.
19. The process of claim 2 , wherein the catalyst comprises niobium, zirconium or scandium.
20. The process of claim 2 , wherein the alcohol is any mono-, di- or multi-functional hydroxyl compound.
21. The process of claim 2 , wherein the alcohol is any mono-, di- or multi-functional C 1-20 alkanol, C 2-20 alkenol, or C 2-20 alkynol.
22. The process of claim 2 , wherein the alcohol is an aromatic alcohol.
23. The process of claim 2 , wherein the alcohol is phenol or benzyl alcohol.