3,5-dimethylcyclohexan-1-one

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 180 g of paraformaldehyde in methanol (500 ml) were slowly added under ice-cooling 230 ml of a 40% solution of methylamine in methanol and 17 ml of acetic acid. After adding dropwise a solution of 250 ml of 3,5-dimethylcyclohexanone in methanol (1 l) thereinto, the resulting mixture was heated under reflux for 5 hours. Then the reaction mixture was cooled to room temperature and the solvent was distilled off under reduced pressure. The residue was acidified by adding dilute hydrochloric acid and then extracted with ethyl acetate. The aqueous layer was made basic by adding sodium hydroxide and then extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate and the solvent was distilled off under reduced pressure. Then the residue was distilled under reduced pressure (100-110° C./1 mmHg) to thereby give 79 g of crude (6R*,8R*)-3,6,8-trimethyl-3-azabicyclo[3.3.1]nonan-9-one as a pale yellow oily substance. the resulting mixture was heated under reflux for 5 hours the solvent was distilled off under reduced pressure by adding dilute hydrochloric acid extracted with ethyl acetate by adding sodium hydroxide extracted with ethyl acetate The organic layer was dried over anhydrous magnesium sulfate the solvent was distilled off under reduced pressure Then the residue was distilled under reduced pressure (100-110° C./1 mmHg)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Reactants: 2-ethynylpyridine (6.0 mmol, 618 mg), 3,5-dimethylcyclohexanone (6.0 mmol, 0.85 mL); yields 2-[(3,5-dimethyl-1-cyclohexen-1-yl)ethynyl]pyridine as a transparent yellow oil (500 mg, 39% overall yield) as a mixture of diastereomers. 1H NMR (CDCl3, 300 MHz) 67 8.57 (m, 1H), 7.62 (m, 1H), 7.40 (m, 1H), 7.19 (m, 1H), 6.15 (br s, 1H), 2.29 (m, 2H), 1.80 (br m, (2H), 1.00 (m, 6H), 0.88 (br m, 2H). MS (EI ionization) 211 (M+).

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In 1,2-dichloroethane (70 ml) were suspended p-nitrobenzylamine hydrochloride (3.8 g), 3,5-dimethylcyclohexanone (2.5 g) and triethylamine (2.8 ml). Under ice-cooling, to the mixture was added sodium triacetoxy boron hydride (5.9 g). Under nitrogen atmosphere, the mixture was stirred at room temperature over night. Under ice-cooling, to the mixture were added 37% formalin (1.8 ml) and sodium triacetoxy boron hydride (5.9 g). Under nitrogen atmosphere, the mixture was stirred at room temperature over night. The solvent was evaporated, and the residue was neutralized with sodium hydroxide. The mixture was extracted with ethyl acetate. The organic layer was washed with water and saturated sodium chloride solution, and dried with anhydrous magnesium sulfate. Under reduced pressure, the solvent was evaporated, and the residue was purified with silica gel column (ethyl acetate/hexane) to give 3 isomers of N-methyl-N-(3,5-dimethylcyclohexyl)-N-(4-nitrobenzyl)-amine (4.3 g; (31-a), 0.7 g; (31-b), 0.2 g; (31-c)) as each yellow oil. Under ice-cooling, to the mixture Under ice-cooling, to the mixture Under nitrogen atmosphere, the mixture was stirred at room temperature over night The solvent was evaporated The mixture was extracted with ethyl acetate The organic layer was washed with water and saturated sodium chloride solution dried with anhydrous magnesium sulfate Under reduced pressure, the solvent was evaporated the residue was purified with silica gel column (ethyl acetate/hexane)