ethyl 5-(cyanomethyl)-1-benzofuran-2-carboxylate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The starting material can be prepared as follows: By the reaction of ethyl 5-chloromethylbenzo[b]furan-2-carboxylate (Chem. Abstr., 1959, 3185d) with excess sodium cyanide in dimethylformamide there is obtained, in a yield of 90% of theory, ethyl 5-cyanomethylbenzo[b]furan-2-carboxylate (m.p. 74°-76° C. after recrystallisation from ethyl acetate) which is hydrogenated in the presence of platinum oxide to give ethyl 5-(2-aminoethyl)-benzo[b]furan-2-carboxylate. From an ethanolic solution thereof, with an ethereal solution of hydrogen chloride there can be precipitated out the hydrochloride; m.p. 188°-190° C.; yield 64% of theory. The starting material can be prepared

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Ethyl 5-cyanomethylbenzofuran-2-carboxylate was hydrolysed by refluxing with ethanolic potassium hydroxide to give 5-cyanomethylbenzofuran-2-carboxylic acid.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of ethyl 5-chloromethylbenzofuran-2-carboxylate (3.0 g, 0.0126 mol), sodium cyanide (1.23 g, 0.025 mol), tetrabutylammonium bromide (0.50 g, 0.0013 mol), water (10 cm3) and dichloromethane (10 cm3) was vigorously stirred for 18 hr. at room temperature. The mixture was separated and the organic layer was washed with water, dried (Na2SO4), filtered and the solvent was removed. The residue was recrystallised from petroleum ether (b.p. 60°-80° C.) to give ethyl 5-cyanomethylbenzofuran-2-carboxylate (1.92 g, 0.0084 mol, 66.6%) m.p. 76°-77° C.-t.l.c./silica/toluene, RF 0.11. at room temperature The mixture was separated the organic layer was washed with water dried (Na2SO4) filtered the solvent was removed The residue was recrystallised from petroleum ether (b.p. 60°-80° C.)

Conditions: temp:0.00; pressure:0.00; stir: