Yield:-

Reaction Conditions:

Stage #1: C₁₄H₂₀N₂Owith lithium aluminium tetrahydride in tetrahydrofuran;Heating / reflux;
Stage #2: with sodium hydroxide;water in tetrahydrofuran;diethyl ether at 20; for 1 h;

Steps:

Intermediate 36

Compound 34 (1.03 g, 4.44 mmol) was dissolved in 10 mL of THF and 1.0 M LAH in THF solution (12.9 mL, 12.9 mmol) was added. This reaction mixture was refluxed overnight. After cooling to room temperature, the mixture was quenched slowly with H2O (0.5 [ML),] 10% [NAOH] solution (0.75 mL), and H20 (1.2 mL). The residue was diluted with 21 mL of ethyl ether and stirred for lh at room temperature. The solid was filtered and washed successively with ethyl ether, [CH2C12,] and ethyl ether. The combined filtrate was dried over [K2C03,] filtered, and concentrated to give an oil. Purification by column chromatography (3% to 20% [MEOH-CH2CL2)] prepared compound 36 as a clear oil.

References:

WO2004/24720,2004,A1 Location in patent:Page 79-80