反应详情

A mixture of the product of Step 2, above (56) (10.81 mmol) and (carbethoxymethyl)triphenylphosphonium bromide (12.0 mmol) in 50 ml of xylene was heated to 155° C. for 20 hours. The reaction was cooled to ambient temperature and concentrated to dryness. The crude residue was chromatographed on silica gel with gradient elution with 5% EtOAc in hexanes to 10% EtOAc in hexanes to obtain the title compound (57).

1. concentrationconcentrated to dryness
2. customThe crude residue was chromatographed on silica gel with gradient elution with 5% EtOAc in hexanes to 10% EtOAc in hexanes