Triacetoxyperiodinane → HCID 58204569, compound

Participants

Reaction Conditions

Reaction Steps

Racemic-trans-3-Hydroxy-4-[2-(2-isopropyl-2H-[1,2,4]triazol-3-yl)-4,5-dihydro-6-oxa-1,3a-diaza-benzo[e]azulen-8-yl]-piperidine-1-carboxylic acid tert-butyl ester from Example 328 (containing approx. 24% of 4-hydroxypiperidine isomer, 0.32 g, 0.65 mmol) was dissolved in DCM (15 mL) and cooled in an ice-bath. Dess-Martin periodinane (0.3 M in DCM, 4.33 mL, 1.3 mmol) was added dropwise, the mixture was stirred at 0-10° C. for 7 h, then refrigerated for 16 h. Aqueous sodium bisulphate and sodium bicarbonate (10 mL each) were added and the mixture was stirred at room temperature for 15 min. The phases were separated and the aqueous phase was extracted twice with DCM. Combined organic extracts were washed with brine, dried (Na2SO4) and concentrated in vacuo. The resultant residue was subjected to flash chromatography (SiO2, gradient 0-5% methanol in DCM) then trituration with ether to give 4-[2-(2-Isopropyl-2H-[1,2,4]triazol-3-yl)-4,5-dihydro-6-oxa-1,3a-diaza-benzo[e]azulen-8-yl]-3-oxo-piperidine-1-carboxylic acid tert-butyl ester (86 mg). Additional product was recovered from the trituration liquor (59 mg). Total yield 145 mg (45%). LCMS RT=3.53, [M+H]+=493, [M+H+ MeOH]+=525.

Provenance & Evidence