Trifluoroacetic acid → 3-Hydroxyisobenzofuran-1(3H)-one

Participants

Reaction Steps

Using a procedure analogous to that used to prepare Example 28, 31D (400 mg, 0.51 mmol) was cyclized with PyBOP instead of BOP, deprotected with TFA, and purified by reverse phase HPLC to give Example 31 (100 mg, 35%) as a tan solid. 1H NMR (400 MHz, CD3OD) δ ppm 1.09-1.24 (m, 3 H) 2.27 (s, 2 H) 2.49 (s, 2 H) 2.67-2.88 (m, 1 H) 3.05-3.17 (m, 1 H) 3.22-3.28 (m, 2 H) 4.05 (d, J=9.89 Hz, 0.5 H) 4.13-4.25 (m, 0.5 H) 4.29-4.39 (m, 1 H) 5.01-5.12 (m, 2 H) 5.14-5.18 (m, J=3.30 Hz, 1 H) 6.43 (none, 1 H) 6.68 (d, J=2.75 Hz, 1 H) 6.70-6.78 (m, J=5.50 Hz, 1 H) 6.78-6.86 (m, 1 H) 6.92-7.16 (m, 2.5 H) 7.21 (m, 0.5 H) 7.44 (m, 0.5 H) 7.51 (s, 0.5 H) 7.65-7.74 (m, 1 H) 7.90-8.02 (m, 1 H) 8.76-8.92 (m, J=6.05 Hz, 1 H). MS (ESI) m/z 574.18 (M+H)+.

Provenance & Evidence