反应详情

To a solution of (R)-3-cyclohexyl-2-(1-oxo-1,3-dihydro-isoindol-2-yl)-propionic acid (prepared in Step A, 144 mg; 0.5 mmol), O-benzotriazol-1-yl-N,N,N′,N′, -tetramethyluronium hexafluorophosphate (BOP, 268 mg; 0.55 mmol) and 2-aminothiazole (50 mg; 0.5 mmol) in dry methylene chloride (3 mL) at room temperature was added N,N-diisopropylethylamine (0.20 mL; 1.15 mmol) dropwise. The mixture was allowed to stir for 1 h. The mixture was then diluted with methylene chloride and washed with water. The organic layer was dried (Na2SO4), filtered and concentrated in vacuo to give a crude residue. Flash chromatography (Merck Silica gel 60, 230-400 mesh, eluent: 30% ethyl acetate/hexanes) provided 150 mg (81%) of (R)-3-cyclohexyl-2-(1-oxo-1,3-dihydro-isoindol-2-yl)-N-thiazol-2-yl-propionamide as an off white foam: EI-HRMS m/e calcd for C20H23N3O2S (M+) 369.1511, found 369.1511.

1. washwashed with water
2. dry with materialThe organic layer was dried (Na2SO4)
3. filtrationfiltered
4. concentrationconcentrated in vacuo
5. customto give a crude residue