Réaction #632023

Équation de réaction

3,3-dimethyl-1,5-dioxaspiro[5.7]tridecan-10-one

1-methyl-3,5-dinitro-1H-pyridin-2-one

ammonia

→

5′,5′-dimethyl-3-nitro-6,8,9,10-tetrahydro-5H-spiro[cycloocta[b]pyridine-7,2′-[1,3]dioxane]

Rendement 92.5%

Solvants

methanol

Conditions de réaction

Traitement

1. 1
   AutreThe solvent was evaporated
2. 2
   workup.DISSOLUTIONthe residue was dissolved in dichloromethane (DCM)
3. 3
   ConcentrationThe soluble portion was concentrated
4. 4
   Autrepurified by flash chromatography on silica gel (hexane/ethyl acetate, 3:1)

Mode opératoire

A mixture of 3,3-dimethyl-1,5-dioxaspiro[5.7]tridecan-10-one (compound of formula (Ca)) (1.32 g, 5.83 mmol), 1-methyl-3,5-dinitro-1H-pyridin-2-one (compound of formula (Cb)) (1.07 g, 5.3 mmol) and 7N ammonia solution in methanol (45 mL) was heated at 80° C. in sealed vessel overnight. The solvent was evaporated and the residue was dissolved in dichloromethane (DCM). The soluble portion was concentrated and purified by flash chromatography on silica gel (hexane/ethyl acetate, 3:1) to give the compound of formula (Cc), 5′,5′-dimethyl-3-nitro-6,8,9,10-tetrahydro-5H-spiro[cycloocta[b]pyridine-7,2′-[1,3]dioxane] (1.5 g, 92.5%); 1H NMR (DMSO-d6, 300 MHz) 9.09 (s, 1H), 8.40 (s, 1H), 3.37 (m, 4H), 3.02 (t, 2H), 2.89 (m, 2H), 2.02 (m, 2H), 1.77 (m, 2H), 1.58 (t, 2H), 0.86 (d, 6H) ppm; MS (ES) 306.99 (M+H).

Source