Formamidine acetate → HCID 70926810, compound

Participants

Reaction Conditions

Reaction Steps

1,1,3,3-Tetramethyl-octahydro-inden-4-one is first prepared by hydrogenating 1,1,3,3-tetramethyl-1,2,3,5,6,7-hexahydro-inden-4-one (prepared as described in U.S. Pat. No. 3,927,083) with Pd/C in alcohol in a Parr Hydrogenator at 25-60° C. and under 500 psi of hydrogen gas. A 100 mL reaction flask is the charged with 1,1,3,3-tetramethyl-octahydro-inden-4-one (10 g, 0.05 mol), formamidine acetate (27 g, 0.26 mol), and butanol (50 mL). The reaction mixture is heated to 130° C. and stirred for 24 hours. The crude mass is washed once with aqueous sulfuric acid (10%, 100 mL) followed by twice with brine (30 mL). Butanol is recovered by roto-evaporation. The crude product is further purified with liquid chromatography (Biotage® system) and then crystallized. Product 1,1,3,3-tetramethyl-2,3,3a,4,5,9b-hexahydro-1H-7,9-diaza-cyclopenta[a]naphthalene (˜5 g) is obtained.

Provenance & Evidence