1,4-Naphthalenedione, 2-bromo- → HCID 10399257, compound

Participants

Reaction Steps

A solution of trans-2-pentenal N,N-dimethylhydrazone (49.15 g, 0.39 mol) in xylene (100 mL) was quickly added to a xylene (600 mL) solution of 2-bromo-1,4-naphthoquinone (71.12 g, 0.30 mol) and the dark reaction heated at reflux for 6 h. Workup followed the procedure described above for cleistopholine. Chromatography provided pure homocleistopholine (13) (10.90 g, 14%). An analytical sample was obtained by crystallization from EtOAc: mp 157°-158° C.; IR (KBr) 1680, 1665, 1590, 1575, 1450, 1340, 1300, 1280, 1260, 1225, 1200, 1000, 955, 870, 850, 800, 790, 730 cm-1 ; 1H NMR (CDCl3) δ1.29 (t, 3 H, J=7.4 Hz), 3.28 (q, 2 H, J=7.4 Hz), 7.48 (d, 1 H, J=5.0 Hz), 7.71-7.78 (m, 2 H), 8.14-8.18 (m, 1 H), 8.25-8.28 (m, 1 H), 8.87 (d, 1 H, J=5.0 Hz); 13C NMR (CDCl3) 14.1 (3), 28.0 (2), 127.1 (1), 127.2 (1), 128.5 (0), 129.3 (1), 132.4 (0), 133.9 (0), 134.0 (1), 134.5 (1), 150.2 (0), 153.6 (1), 157.2 (0), 181.8 (0),

Provenance & Evidence