反应详情

To a solution of (3S)-2-[(2R)-3-cyclopentyl-2-({formyl[(phenylmethyl)oxy]amino}methyl)propanoyl]-1-{[(phenylmethyl)oxy]carbonyl}-3-pyrazolidine carboxylic acid (103.1 mg, 0.192 mmol), 1H-1,2,3-benzotriazol-5-amine (56.6 mg, 0.422 mmol), and N-methylmorpholine (46.4 μl, 0.422 mmol) in acetonitrile (1.87 ml) was added DMTMM tetrafluoroborate (69.2 mg, 0.211 mmol). The solution was stirred for 3 days, and then concentrated in vacuo. The residue was dissolved in EtOAc (100 mL), and washed with 1 N aq. HCl (50 mL), followed by 5% aq. NaHCO3. The organic phase was dried over anhydrous Na2SO4, filtered, and concentrated in vacuo. The residue was purified by Gilson RPLC (20% to 90% MeCN in water, 8 min gradient), and the desired fractions were combined, and concentrated in vacuo. The residue was azeotroped with MeOH (2×30 mL) to give phenylmethyl (3S)-3-[(1H-1,2,3-benzotriazol-5-ylamino)carbonyl]-2-[(2R)-3-cyclopentyl-2-({formyl[(phenylmethyl)oxy]amino}methyl)propanoyl]-1-pyrazolidinecarboxylate (87.2 mg, 0.133 mmol, 69.6% yield) as a light yellow oil. LC/MS: (M+H)+: 654.5. Reference for DMTMM tetrafluoroborate: Raw, S. A. Tetrahedron Lett. 2009, 50, 946.

1. concentrationconcentrated in vacuo
2. dissolutionThe residue was dissolved in EtOAc (100 mL)
3. washwashed with 1 N aq. HCl (50 mL)
4. dry with materialThe organic phase was dried over anhydrous Na2SO4
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customThe residue was purified by Gilson RPLC (20% to 90% MeCN in water, 8 min gradient)
8. concentrationconcentrated in vacuo
9. customThe residue was azeotroped with MeOH (2×30 mL)