反应详情

This compound was prepared according to procedures described for similar compounds (i.e. 2-bromo-1-naphthols) as reported by G. R. Green et. al. (Tetrahedron, (1998), 54, 9875-9894), with modification. To a stirred solution of 3-methyl-6-(methyloxy)-3,4-dihydro-1(2H)-naphthalenone (12) (4.80 g, 25.2 mmol) in CHCl3 (130 mL) was slowly added dropwise a solution of Br2 (8.12 g, 50.81 mmol, 2.02 eq) in CHCl3 (60 mL) over a period of 4 h at RT under N2. The reaction mixture was stirred overnight. The reaction mixture was concentrated to give 9.82 g of crude 2,2-dibromo-3-methyl-6-(methyloxy)-3,4-dihydro-1(2H)-naphthalenone as a dark brown-orange oil [1H NMR (400 MHz; CDCl3): δ 1.49 (d, J=6.3 Hz, 3H), 2.56 (m, 1H), 2.91 (m, 2H), 3.86 (s, 3H), 6.67 (d, J=2.2 Hz, 1H), 6.90 (dd, J=2.5 Hz, 8.9 Hz, 1H), 8.14 (d, J=8.8 Hz, 1H)]. A solution of 2,2-dibromo-3-methyl-6-(methyloxy)-3,4-dihydro-1(2H)-naphthalenone (9.8 g, 25.2 mmol) in CH3CN (160 mL) was cooled in an ice-water bath to 0-5° C. and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) (6 mL, 6.11 g, 39.6 mmol, 1.57 eq) was added slowly dropwise under N2. The ice-water bath was removed and the reaction mixture was allowed to stir at RT under N2 for 40 min. To the reaction mixture was added 1 N HCl (160 mL) and the aqueous mixture was extracted with CH2Cl2 (2×). The organic extracts were combined, washed with H2O (2×), dried over MgSO4, filtered, and the filtrate was concentrated to give 6.8 g (100%) of the title compound 13 as a solid. 1H NMR (400 MHz; d6-DMSO-d6): δ 2.43 (s, 3H), 3.83 (s, 3H), 7.07 (dd, J=2.2 Hz, 9.2 Hz, 1H), 7.16 (d, J=2.2 Hz, 1H), 7.29 (s, 1H), 8.04 (d, J=9.1 Hz, 1H), 9.66 (s, 1H).

1. customThe ice-water bath was removed
2. additionTo the reaction mixture was added 1 N HCl (160 mL)
3. extractionthe aqueous mixture was extracted with CH2Cl2 (2×)
4. washwashed with H2O (2×)
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. concentrationthe filtrate was concentrated