1-Hydroxybenzotriazole → HCID 70045463, compound

Participants

Reaction Steps

To a solution of the product of Example 2, starting material step (c) (470 mg), HBTU (460 mg) and HOBT (190 mg) in DMF (3 ml) under argon was added diisopropylethylamine (0.63 ml). After 2-3 minutes the resultant pale yellow reaction mixture was added to benzyl 2-methylcarbazate (Dutta, A.S. et al (1975), J. Chem. Soc. Perkin Trans. I, 1712-20) (200 mg). The reaction mixture was stirred at ambient temperature under argon for 3.5 hours then diluted with ethyl acetate (50 ml) and washed with water, dilute KHSO4 (aq.) and dilute NaOH (aq.) and water, dried (MgSO4) and evaporated to give benzyl 2-methyl-3-(3,4-di-t-butoxycarbonylmethoxybenzoyl)carbazate (0.61 g) as a glass; NMR Spectrum (DMSO--d6) 1.43 (18H, s), 3.13 (3H, br s), 4.70 (2H, s), 4.75 (2H, s), 5.02-5.20 (2H, br), 6.99 (1H, m), 7.20-7.50 (7H, m), 10.68 (1H, br); Mass Spectrum m/Z 544 (M+). In the ambient temperature NMR spectrum, ancillary signals attributable to rotamers were observed.

Provenance & Evidence