9-{4-[4-(Trifluoromethyl)phenoxy]phenyl}-3,4-dihydropyrido[2,1-c][1,2,4]thiadiazine 2,2-dioxide → 9-{4-[4-(Trifluoromethyl)phenoxy]phenyl}-3,4,6,7,8,9-hexahydropyrido[2,1-c][1,2,4]thiadiazine 2,2-dioxide

Participants

Reaction Steps

To a suspension of NaH (60%, 418 mg) in THF (dry) (25 mL) was added 2-chloroethanesulfonyl chloride (0.659 mL) at 0° C. and the mixture was stirred for 5 min at the same temperature. A solution of 3-(4-(4-(trifluoromethyl)phenoxy)phenyl)pyridin-2-amine (690 mg) in THF (dry) (40 mL) was added at 0° C. and the mixture was stirred at room temperature overnight. The mixture was quenched with water at 0° C. Water, EtOAc and THF were added and the extracted organic layer was washed with brine, dried over anhydrous magnesium sulfate and concentrated in vacuo. The residue was washed with IPE/EtOAc, dried in vacuo to give 9-{4-[4-(trifluoromethyl)phenoxy]phenyl}-3,4-dihydropyrido[2,1-c][1,2,4]thiadiazine 2,2-dioxide (579.1 mg) as a slightly yellow solid. Platinum(IV) oxide (30 mg) was added to a solution of 9-{4-[4-(trifluoromethyl)phenoxy]phenyl}-3,4-dihydropyrido[2,1-c][1,2,4]thiadiazine 2,2-dioxide (505 mg) in THF (dry) (15 mL) and MeOH (15 mL) and the mixture was stirred at room temperature under hydrogen for 6 hr. Platinum(IV) oxide (30 mg), MeOH (15 mL) and THF (dry) (15 mL) were added and the mixture was stirred at 50° C. under hydrogen overnight. Activated carbon was added and the insoluble solid was removed by filtration through NH-silica gel/Celite pad (eluted with EtOAc) and the filtrate was concentrated in vacuo. The residue was crystallized from THF/IPE to give the title compound (297.2 mg) as colorless crystals.

Provenance & Evidence