Ammonia → 3',3'-dimethyl-8'-(pyrrolidin-1-ylsulfonyl)-3',4'-dihydro-2'H-spiro[1,3-dioxane-2,10'-pyrimido[1,2-a]indole]

Participants

Reaction Conditions

Reaction Steps

A mixture of 2,2-dimethyl-3-[2′-oxo-5′-(pyrrolidin-1-ylsulfonyl)spiro[1,3-dioxane-2,3′-indol]-1′(2′H)-yl]propanenitrile (0.69 g, 1.64 mmol) and wet Raney Nickel (0.70 g) in 2M EtOH.NH3 (50 mL) and THF (20 mL) was hydrogenated in a Parr hydrogenation bottle (500 mL) at 541 b/in2 hydrogen for 67 hr. The Raney Nickel was removed by filtration through Sulka Floc and the filtrate was poured into a steel pressure vessel, diluted with 2M EtOH.NH3 (50 mL) and THF (20 mL) and heated at 135° C. for 22 hr. The reaction was cooled to room temperature and concentrated. The crude product was purified on Biotage KP silica gel eluting with CH2Cl2/CH3OH/NH4OH (98.5/1/.05) to give the title compound as a white solid (0.300 g, 45% yield). NMR: consistent. MS: (API-ES+) m/z 406 [M+H].

Provenance & Evidence