Octyl cyanoacetate

Colorless liquid

To a solution of octyl triflate (0.05 mol) in dry dichloromethane (DCM, 100 mL) was added trifluoroacetic acid [TFA] (0.004 mol) and t-butylated hydroxyanisole (0.25 wtpercent). A solution of Dicyclohexylammonium alpha-cyanoacrylate in dry DCM (80mL) was added dropwise (2h). The resulting solution was stirred at 22 °C overnight. NMR showed approx 10percent of the triflate remaining with no trace of polymer. A solution of 0.078 mol of Dicyclohexylammonium alpha-cyanoacrylate in dry DCM (20 mL) was added. The mixture was stirred at 22 °C until triflate had disappeared in the NMR (4h). The mixture was acidified (TFA) and reduced in vacuo. The precipitated solid was removed by filtration. Hexane (100 mL) was added. The mixture was reduced and filtered again. This was repeated. The solvents were removed to afford 1 1.5g of a yellow liquid which was -75- 80percent CA monomer. The impurities are cyanoacrylic acid (due to the excess ofDicyclohexylammonium alpha-cyanoacrylate used), dioctyl ether (a byproduct carried through from the triflate formation) a small amount (<2percent) of polymer, trace amounts of the amine triflate salt, octyl cyanoacetate (formed from cyanoacetic acid amine salt, a residue from incomplete formation of the Dicyclohexylammonium alpha-cyanoacrylate). There are no byproducts or side reaction evident from the CA formation reaction. The octyl CA was distilled to purify and afforded an overall yield of 65percent based on triflate. The synthesis procedure is general and has been used to prepare crude samples of other monomers such as n-propyl CA, 3-methoxybutyl CA and bis-cyanoacrylic acid ester of PEG 400.[0060] NMR Analysis of distilled material:

Molecular Weight:197.27
XLogP3:3.3
Hydrogen Bond Acceptor Count:3
Rotatable Bond Count:9
Exact Mass:197.141578849
Monoisotopic Mass:197.141578849
Topological Polar Surface Area:50.1
Heavy Atom Count:14
Complexity:193
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes