... Page 2. 2690 J. Org. Chem., Vol. 57, No. 9, 1992 ... The organic layer was dried over MgSO, and evaporated to leave 4.0 g of crude product which was purified on a RP-18 reversed-phase column (240 g) with methanol/water (8515) to yield 3.07 g (72%) of the product. ...