Hydrochloric Acid → HCID 67713892, compound

Participants

Reaction Steps

(5R)-1-Azabicyclo[3.2.1]octan-6-one (-)camphorsulfonate (61.8 g, 135.0 mmol) and triethylamine (20.4 g, 202 mmol) and ethyl cyanoacetate (61.8 g, 547 mmol) were mixed and stirred at room temperature for 6 days. Toluene (120 ml) and water (120 ml) were added to the reaction mixture and the pH was adjusted to 2 with concentrated hydrochloric acid. The phases were separated and the water phase extracted with toluene (30 ml). The combined organic phases were washed with water (20 ml). The combined water phases were adjusted to pH=9.4 with NH3 (25% in water) and extracted with toluene (1×120 ml, 1×60 ml). The combined toluene extracts were evaporated. The residue was dissolved in ethanol (120 ml) and concentrated hydrochloric acid (16 ml) was added. The title compound precipitated in 22 g yield. Upon evaporation of the mother liquor and crystallization from ethanol (40 ml) further 14.6 g of the title compound was isolated.

Provenance & Evidence