1-(benzyloxycarbonyl)-6-Methylpiperidine-3-carboxylic acid synthesis

Yield:908245-09-0 95.5%

Reaction Conditions:

Stage #1: C₁₆H₂₁NO₄with lithium hydroxide;water in tetrahydrofuran at 20; for 16 h;
Stage #2: with hydrogenchloride in tetrahydrofuran;water; pH=2.7;

Steps:

B

A 100-mL, one-neck, round-bottomed flask was charged with tetrahydrofuran (15 mL), water (30 mL), lithium hydroxide (0.35 g, 14.6 mmol) and 6-Me-3 (3.25 g, 11.2 mmol). The mixture was stirred at ambient temperature for 16 hours. The mixture was treated with HCl to adjust the pH to pH 2.7. The liquors were extracted with ethyl acetate (2 x 50 mL). The ethyl acetate extracts were combined and dried over anhydrous magnesium sulfate, then the mixture was filtered. The filtrate was evaporated under reduced pressure to give a 6-Me-3 acid (3.0 g, 95.5%): HPLC (Method A) 90.7% (AUC), t_R = 4.78 min.

References:

WO2006/91697,2006,A1 Location in patent:Page/Page column 34