Formaldehyde → HCID 69285461, compound

Participants

Reaction Steps

The crude mixture of tert-butyl 3-((1R,2S,5R)-5-amino-2-(2-(3-(trifluoromethyl)benzamido)acetamido)cyclohexyl)propanoate and 3-((1R,2S,5R)-5-amino-2-(2-(3-(trifluoromethyl)benzamido)acetamido)cyclohexyl)propanoic acid prepared in Example 7a, Step 6 was dissolved in 1,2-dichloroethane (2 mL) and treated sequentially with acetone (32 μL), acetic acid (25 μL) and sodium triacetoxyborohydride (92 mg). The mixture was stirred at rt for 19.5 h, then was treated with aqueous formaldehyde (33 μL). After 1.5 h, additional aqueous formaldehyde (20 μL) and sodium triacetoxyborohydride (50 mg) were added and the mixture was stirred for an additional 2.5 h. The mixture was concentrated under vacuum and the residue was partitioned between saturated aqueous NaHCO3 and ethyl acetate. The aqueous phase was extracted twice with ethyl acetate and the combined organic phases were dried over Na2SO4 and concentrated under vacuum to provide the title product, tert-butyl 3-((1R,2S,5R)-5-(isopropyl(methyl)amino)-2-(2-(3-(trifluoromethyl)benzamido)acetamido)cyclohexyl)propanoate, as a glassy foam (45 mg). MS found: (M+H)+=528.4.

Provenance & Evidence