5-bromo-2,2-dimethyl-3H-1-benzofuran

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: This compound is prepared in a manner analogous to that of Step D of Example 7, using 9.2 grams (0.040 mole) of 5-bromo-2,3-dihydro-2,2-dimethylbenzofuran, 1.1 grams (0.044 mole) of magnesium turnings, and 6.2 grams (0.040 mole) of 1,4-cyclohexanedione mono-ethylene ketal in about 70 mL of tetrahydrofuran, yielding 1-(2,3-dihydro-2,2-dimethylbenzofuran-5-yl)-1-cyclohexen-4-one. This compound is prepared in a manner analogous to that of Step D of Example 7

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: This compound is prepared in a manner analogous to that of Step D of Example 7, using 9.2 grams (0.040 mole) of 5-bromo-2,3-dihydro-2,2-dimethylbenzofuran, 1.1 grams (0.044 mole) of magnesium turnings, and 6.2 grams (0.040 mole) of 1,4-cyclohexanedione mono-ethylene ketal in about 70 mL of tetrahydrofuran, yielding 1-(2,3-dihydro-2,2-dimethylbenzofuran-5-yl)-1-cyclohexen-4-one. This compound is prepared in a manner analogous to that of Step D of Example 7

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2,2-Dimethyl-2,3-dihydrobenzo[b]furan (prepared according to the method of Baker and Shulgin, J. Org. Chem., 28, 1963, 2468) (500 mg, 3.38 mmol) was taken up in dichloroethane (5.5 ml) and stirred at room temperature under nitrogen, and N-bromosuccinimide (661 mg, 3.72 mmol) added in one portion. The reaction was then refluxed for 2 h, ether was added (10 ml) and a white precipitate of succinimide filtered off. The filtrate was evaporated to dryness, and then purified by column chromatography using 5% ether in pentane as eluant to give the title product (604 mg, 79%); 1HNMR (400 MHz, CDCl3) δ: 1.43 (s, 6H), 2.92 (s, 2H), 6.54 (d, 1H), 7.16 (d, 1H), 7.19 (s, 1H); LRMS: M+H, 227. (TS+). The reaction was then refluxed for 2 h a white precipitate of succinimide filtered off The filtrate was evaporated to dryness purified by column chromatography

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2,2-Dimethyl-2,3-dihydrobenzo[b]furan (prepared according to the method of Baker and Shulgin, J. Org. Chem., 28, 1963, 2468) (500 mg, 3.38 mmol) was taken up in dichloroethane (5.5 ml) and stirred at room temperature under nitrogen, and N-bromosuccinimide (661 mg, 3.72 mmol) added in one portion. The reaction was then refluxed for 2 h, ether was added (10 ml) and a white precipitate of succinimide filtered off. The filtrate was evaporated to dryness, and then purified by column chromatography using 5% ether in pentane as eluant to give the title product (604 mg, 79%); 1HNMR (400 MHz, CDCl3) δ: 1.43 (s, 6H), 2.92 (s, 2H), 6.54 (d, 1H), 7.16 (d, 1H), 7.19 (s, 1H); LRMS: M+H, 227. (TS+). The reaction was then refluxed for 2 h a white precipitate of succinimide filtered off The filtrate was evaporated to dryness purified by column chromatography

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2,2-Dimethyl-2,3-dihydrobenzo[b]furan (prepared according to the method of Baker and Shulgin, J. Org. Chem., 28, 1963, 2468) (500 mg, 3.38 mmol) was taken up in dichloroethane (5.5 ml) and stirred at room temperature under nitrogen, and N-bromosuccinimide (661 mg, 3.72 mmol) added in one portion. The reaction was then refluxed for 2 h, ether was added (10 ml) and a white precipitate of succinimide filtered off. The filtrate was evaporated to dryness, and then purified by column chromatography using 5% ether in pentane as eluant to give the title product (604 mg, 79%); 1HNMR (400 MHz, CDCl3) δ: 1.43 (s, 6H), 2.92 (s, 2H), 6.54 (d, 1H), 7.16 (d, 1H), 7.19 (s, 1H); LRMS: M+H, 227. (TS+). The reaction was then refluxed for 2 h a white precipitate of succinimide filtered off The filtrate was evaporated to dryness purified by column chromatography

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 4-bromo-2-(2-methylallyl)phenol (7) (4.5 g, 19.8 mmol) in CH2Cl2 (250 mL) was added iodine (1.3 g, 4.95 mmol) and the mixture stirred at room temperature for 48 h. The mixture was then diluted with methyl tert-butyl ether (100 mL) and washed with H2O (50 mL), brine (50 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was purified by flash chromatography (silica gel, eluting with 5% ethyl acetate in hexanes) to give the title compound (8) (4.0 g, 88%) as yellow liquid. 1H NMR (CDCl3, 400 MHz) δ 7.24 (s, 1H), 7.20 (d, J=8.4 Hz, 1H), 6.61 (d, J=8.4 Hz, 1H), 3.00 (s, 2H), 1.47 (s, 6H); MS (ESI, M+H+) C10H12BrO, calcd. 227.1. found 227.0, 229.0. washed with H2O (50 mL), brine (50 mL) dried over anhydrous sodium sulfate concentrated under reduced pressure The residue was purified by flash chromatography (silica gel, eluting with 5% ethyl acetate in hexanes)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: This compound is prepared in a manner analogous to that of Step D of Example 7, using 9.2 grams (0.040 mole) of 5-bromo-2,3-dihydro-2,2-dimethylbenzofuran, 1.1 grams (0.044 mole) of magnesium turnings, and 6.2 grams (0.040 mole) of 1,4-cyclohexanedione mono-ethylene ketal in about 70 mL of tetrahydrofuran, yielding 1-(2,3-dihydro-2,2-dimethylbenzofuran-5-yl)-1-cyclohexen-4-one. This compound is prepared in a manner analogous to that of Step D of Example 7

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: This compound is prepared in a manner analogous to that of Step D of Example 7, using 9.2 grams (0.040 mole) of 5-bromo-2,3-dihydro-2,2-dimethylbenzofuran, 1.1 grams (0.044 mole) of magnesium turnings, and 6.2 grams (0.040 mole) of 1,4-cyclohexanedione mono-ethylene ketal in about 70 mL of tetrahydrofuran, yielding 1-(2,3-dihydro-2,2-dimethylbenzofuran-5-yl)-1-cyclohexen-4-one. This compound is prepared in a manner analogous to that of Step D of Example 7

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2,2-Dimethyl-2,3-dihydrobenzo[b]furan (prepared according to the method of Baker and Shulgin, J. Org. Chem., 28, 1963, 2468) (500 mg, 3.38 mmol) was taken up in dichloroethane (5.5 ml) and stirred at room temperature under nitrogen, and N-bromosuccinimide (661 mg, 3.72 mmol) added in one portion. The reaction was then refluxed for 2 h, ether was added (10 ml) and a white precipitate of succinimide filtered off. The filtrate was evaporated to dryness, and then purified by column chromatography using 5% ether in pentane as eluant to give the title product (604 mg, 79%); 1HNMR (400 MHz, CDCl3) δ: 1.43 (s, 6H), 2.92 (s, 2H), 6.54 (d, 1H), 7.16 (d, 1H), 7.19 (s, 1H); LRMS: M+H, 227. (TS+). The reaction was then refluxed for 2 h a white precipitate of succinimide filtered off The filtrate was evaporated to dryness purified by column chromatography

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2,2-Dimethyl-2,3-dihydrobenzo[b]furan (prepared according to the method of Baker and Shulgin, J. Org. Chem., 28, 1963, 2468) (500 mg, 3.38 mmol) was taken up in dichloroethane (5.5 ml) and stirred at room temperature under nitrogen, and N-bromosuccinimide (661 mg, 3.72 mmol) added in one portion. The reaction was then refluxed for 2 h, ether was added (10 ml) and a white precipitate of succinimide filtered off. The filtrate was evaporated to dryness, and then purified by column chromatography using 5% ether in pentane as eluant to give the title product (604 mg, 79%); 1HNMR (400 MHz, CDCl3) δ: 1.43 (s, 6H), 2.92 (s, 2H), 6.54 (d, 1H), 7.16 (d, 1H), 7.19 (s, 1H); LRMS: M+H, 227. (TS+). The reaction was then refluxed for 2 h a white precipitate of succinimide filtered off The filtrate was evaporated to dryness purified by column chromatography