Hydrochloric Acid → HCID 66736794, compound

Participants

Reaction Conditions

Reaction Steps

A solution of (3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl)-carbamic acid benzyl ester (prepared according to method C, 1.4 g, 4.7 mmol) and intermediate 4.i (0.984 g, 4.7 mmol) in DMF (15 mL) at 0° C. was treated dropwise with a 2.2M solution of t-BuOLi in THF (6.4 mL, 3 eq.). The mixture was stirred at 0° C. for 1 h and at rt overnight. 1M HCl (9.4 mL) was added and the mixture partitioned between EA and water. The aq. phase was extracted once more with EA and the combined org. phases were washed several times with water and brine, dried over MgSO4 and concentrated. The residue was purified by FC (Hept/EA 1:2, EA) to give the title intermediate as a colourless solid (0.5 g, 29% yield).

Provenance & Evidence