Nitric Acid → HCID 19045439, compound

Participants

Reaction Conditions

Reaction Steps

A mechanically stirred solution of N(2-(4-aminophenyl)ethyl)-1,4-dioxa-8-azaspiro[4.5]-decane in methylene chloride (400 mL) cooled to -5° C. under an argon atmosphere was treated dropwise with acetic anhydride (58.8 mL, 622 mmoles). The reaction was allowed to reach room temperature and was stirred for 18 hr. After the addition of an additional 29.5 mL (312 mmoles) of acetic anhydride, the reaction was cooled to -5° C., and a solution of nitric acid (d=1.49, 22.0 mL, 468 mmoles) in methylene chloride (1:1 by volume) was added dropwise. The reaction mixture was allowed to reach room temperature and was stirred for 4 hours. The mixture was cooled in an ice bath and 100 mL of saturated brine was added. The layers were separated and the aqueous phase was extracted with methylene chloride. The combined organic portion was dried (Na2SO4), concentrated and flushed with toluene (3×200 mL). The crude product crystallized during concentration, was filtered, and triturated with ethyl acetate (550 mL) to yield 56.7 g (89%) of N(2-(4-acetamino-3-nitrophenyl)ethyl)-1,4-dioxa-8-azaspiro[4.5]-decane acetic acid salt. TLC Rf=0.80 (silica gel, 5% methanol in methylene chloride saturated with ammonia).

Provenance & Evidence