反应详情

20-2 (486 mg; 1.6 mmol) and 10-4 (250 mg, 1.6 mmol) were dissolved in CH2Cl2. PYCLU (1.8 mmol, 634 mg) was added, followed by diisopropylethylamine (6.4 mmol, 1.1 mL). The reaction is stirred for 2 days. The reaction mixture is diluted with EtOAc and washed with H2 O, 10% KHSO4, sat NaHCO3 and brine. The organic layer is dried (MgSO4), filtered and concentrated to yield a tan oil. Flash chromatography (10% MeOH/CHCl3 sat NH3) yielded desired product (20-3) plus bis piperidine urea by-product. This material is triturated with hexane to remove most of the by-product.

1. washwashed with H2 O, 10% KHSO4
2. dry with materialThe organic layer is dried (MgSO4)
3. filtrationfiltered
4. concentrationconcentrated
5. customto yield a tan oil