Benzene, 1-bromo-4-(trifluoromethyl)- → 4-Tetrahydropyranyloxy-4'-trifluormethyltolan

Participants

Reaction Conditions

Reaction Steps

A solution of 3 (12.1 g, 60 mmol) and 4-bromobenzotriflouride (14.85 g, 66 mmol) in diisopropylamine (250 ml) was heated to 30° C. under nitrogen, and the solution was degassed. Then Pd(PPh3)2Cl2 (210 mg, 0.3 mmol) and copper(I) iodide (114 mg, 0.6 mmol) were added to this clear solution. The reaction mixture was stirred for 2 hours at 80° C., and then cooled to room temperature. The salt formed during the reaction procedure was filtered off and washed well with ethyl acetate. The filtrate was evaporated to dryness and hydrolyzed with concentrated hydrochloric acid (10 ml), water (100 ml) and crushed ice (50 g), then extracted with ethyl acetate. The combined organic paste was washed with brine and dried over MgSO4. The solvent was removed in vacuo and the residue was purified by column chromatography (petroleum ether-ethyl acetate=9:1) to give a pale yellow crystals of 4. Yield 16.6 g (80%); mp 112˜113° C.; δH (CDCl3, 300 MHz): 7.59 (s, 4H, Ar—H), 7.48 (d, J=8.7, 2H, Ar—H), 7.04 (d, J=8.7, 2H, Ar—H), 5.46 (t, J=3.1, 1H, OCHO), 3.89 (m, 1H, THP), 3.62 (m, 1H, THP), 1.86˜1.62 (m, 6H, THP).

Provenance & Evidence