Hydrochloric Acid → HCID 66813374, compound

Participants

Reaction Steps

4′-[(2-t-Butoxycarbonylaminoethyl)pentanoylamino]methylbiphenyl-2-carboxylic acid t-butyl ester (3b) and 4′-[(2-aminoethyl)pentanoylamino]methylbiphenyl-2-carboxylic acid (3c): Valeryl chloride (4.6 mL, 38.7 mmol) was added to a solution of crude intermediate (3a) (15 g, 35.2 mmol) in toluene (100 mL) at 0° C. followed by the addition of DIPEA (18.4 mL, 105 mmol). The mixture was stirred at room temperature for 3 hours. 1M aqueous NaOH (10 mL) was added and the mixture was concentrated in vacuo. The concentrate was extracted with EtOAc (3×150 mL) and water (80 mL). The organic extracts were dried over Na2SO4, filtered, and concentrated in vacuo to afford crude intermediate (3b). A solution of crude intermediate (3b), 1,4-dioxane (50 mL) and 4M HCl in 1,4-dioxane (50 mL) was stirred for 40 minutes at room temperature. The precipitate was filtered and purified by reverse phase HPLC to afford intermediate (3c).

Provenance & Evidence