4-AMINO-CHROMAN-8-CARBONITRILE HYDROCHLORIDE synthesis

Yield:-

Reaction Conditions:

Stage #1: 4-oxo-3,4-dihydro-2H-chromene-8-carbonitrilewith ammonium acetate;sodium cyanoborohydride in methanol; for 120 h;Molecular sieve;
Stage #2: with hydrogenchloride in water;
Stage #3: with sodium hydroxide in water; pH=10;

Steps:

33

4-Amino-3,4-dihydro-2H-chromene-8-carbonitrile. A mixture of 260 mg of 4-oxo-3,4-dihydro-2H-chromene-8-carbonitrile (made from 2-hydroxybenzonitrile via the procedure described in Example 29), ammonium acetate (1.2 g), and 3 A molecular sieves (1.5 g) in 10 mL of methanol was stirred for 5 days. The mixture was filtered through celite and the filtrate concentrated in vacuo. The crude residue was treated with 100 mL of 1 M HCl and extracted with ethyl ether (3 X 100 mL). The aqueous layer was made basic to pH 10 with saturated NaOH and extracted with DCM (3 X 100 mL). The combined DCM layers were washed with brine, dried over magnesium sulfate, and concentrated in vacuo to provide 150 mg of the title compound.

References:

WO2006/108103,2006,A1 Location in patent:Page/Page column 101