Maleimide → HCID 44475354, compound

Participants

Reaction Steps

Diisopropyl azodicarboxylate (730 μL, 3.43 mmol) was added dropwise into the ice cooled solution of 3,6,9,12,15,18-hexaoxahenicos-20-yn-1-ol 1 (1000 mg, 3.12 mmol), triphenylphosphine (900 mg, 3.43 mmol) and maleimide (456 mg, 4.70 mmol) in anhydrous THF (20 mL) under nitrogen atmosphere (FIG. 3). The resulting brown solution was allowed to war to room temperature and stirred for 1 hour at room temperature. The solvent was evaporated at the reduced pressure and the crude product was purified on a SiO2 column using hexanes/ethylacetate gradient 0-100% to yield 650 mg of yellow oil which was subsequently purified on semipreparative HPLC (System E) to provide 2 free of triphenylphosphine oxide as colorless oil 310 mg (25%). 1H NMR (400 MHz, CDCl3): δ 2.43 (t, J=2.36 Hz, 1H), 3.60-3.72 (m, 24H), 4.20 (d, J=2.37 Hz, 2H), 6.70 (s, 2H); 13C NMR (100.6 MHz, CDCl3): δ 37.2, 58.4, 67.8, 69.1, 70.1, 70.4-70.6, 74.5, 79.7, 134.1, 170.6; MS ESI (m/z): [M+H]+, calcd. for C19H30NO8, 400.19. found 400.0

Provenance & Evidence