HCID 123957772, compound → HCID 123292264, compound

Participants

Reaction Steps

To a solution of tert-butyl ((3aR,5S,6S,7aR)-6-(benzyloxy)-5-formyl-5,6,7,7a-tetrahydro-3aH-pyrano[3,2-d]thiazol-2-yl)(methyl)carbamate (0.920 g, 2.26 mmol) in anhydrous THF (20 mL) at 15° C. was added a solution of MeMgBr (1.4 M in THF/toluene, 4.1 mL, 5.7 mmol) dropwise. The reaction mixture was stirred at room temperature for 3 h, and then quenched with saturated aqueous NaHCO3 solution (30 mL). The mixture was extracted with EtOAc (2×30 mL), and the combined extracts were dried over anhydrous Na2SO4. After filtration the solvent was evaporated under reduced pressure, and the residue was purified on silica gel by automatic flash column chromatography (MeOH/DCM, 0:4 to 1:4), affording tert-butyl ((3aR,5R,6S,7aR)-6-(benzyloxy)-5-(1-hydroxyethyl)-5,6,7,7a-tetrahydro-3aH-pyrano[3,2-d]thiazol-2-yl)(methyl)carbamate (0.350 g, 37%) as a white foam; 1H NMR (400 MHz, CDCl3) for this material indicated that it contained two diastereomers with a ratio of 1:2. Also isolated was the deprotected side product 1-((3aR,5R,6S,7aR)-6-(benzyloxy)-2-(methylamino)-5,6,7,7a-tetrahydro-3aH-pyrano[3,2-d]thiazol-5-yl)ethanol (0.300 g, 41%) as a white solid; 1H NMR (400 MHz, CDCl3) for this material indicated that it contained two diastereomers with a ratio of 1:1.4.

Provenance & Evidence