Hydrochloric Acid → HCID 13443699, compound

Participants

Reaction Steps

A solution of 6,7-dimethyl-2-methoxy-4a,5,8,8a-tetrahydronaphthalene-1,4-dione (4.0 g, 18.2 mmol) in MeOH (600 mL) was purged with a stream of N2 for 10 min with stirring at rt. With continued N2 purging, solid K2CO3 (2.51 g, 18.2 mmol, Baker) was added to the stirred solution. The solution immediately turned yellow. The reaction was allowed to stir for 30 min at rt under N2, after which it was brown. To this there was added a dilute HCl solution (10% concd HCl, 90% H2O, 200 mL) in one portion. The MeOH was removed in vacuo to give a colorless suspension. The suspension was cooled in an ice bath for 20 min. The suspended material was collected by filtration, washed with a dilute acid solution (as above, 3×20 mL) and dried in vacuo to yield a fluffy colorless solid (3.90 g, 98%, pure by 1H NMR analysis (unstable on TLC)); mp 200-°201° C.; 1H NMR (CDCl3) δ1.79 (s, 6H), 3.12 (m, 2H), 3.25 (m, 2H), 3.83 (s, 3H), 4.25 (s, 1H), 5.25 (s, 1H), 6.35 (s, 1H).

Provenance & Evidence