HCID 129225519, compound → HCID 131729885, compound

Participants

Reaction Conditions

Reaction Steps

CrO3 (8.0 g, 100 wt %, 80.0 mmol) is added to a solution of Compound 1.19 (8.0 g, 18.6 mmol) in AcOH (150 mL). The resulting reaction mixture is heated at 60° C. for about 24-36 h. Upon complete disappearance of the precursor, acetic acid is evaporated under vacuum, and the crude material is dissolved in diethyl ether (400 mL). The organic layer is washed with water (2×100 mL), saturated brine solution (100 mL) and dried over MgSO4 (40 g). The solvent is removed under vacuum and the crude material is purified by column chromatography [49(W)×600(L) mm, 60-120 Mesh silica, 120 g] eluting with ethyl acetate/hexane (1:5) [10 mL fractions, 3 mL/min elution, monitored by TLC and detected with UV light (254 nm) lamp; Rf for Compound 1.20=0.28 and Rf for Compound 1.19=0.61 in EtOAc/Hexane (1:4)] to afford Compound 1.20 (5 g, 60.5% yield) as a colorless solid. Table 9 describes the measured properties of the product.

Provenance & Evidence