5-ethylbenzene-1,3-diol

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

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: 1,3-Dimethoxy-5-ethylbenzene (7.69 g) is dissolved in acetic acid (80 ml), and thereto is added with stirring 47% hydrobromic acid at room temperature. The mixture is refluxed for three hours, and the reaction mixture is cooled to room temperature. The mixture is concentrated to dryness under reduced pressure, and the residue is dissolved in ethyl acetate. The organic layer is washed successively with water and a saturated aqueous sodium chloride solution, dried, and concentrated under reduced pressure. The residue is recrystallized from diisopropyl ether-hexane to give 1,3-dihydroxy-5-ethylbenzene (5.94 g), m.p. 97-98° C. is added The mixture is refluxed for three hours The mixture is concentrated to dryness under reduced pressure the residue is dissolved in ethyl acetate The organic layer is washed successively with water a saturated aqueous sodium chloride solution, dried concentrated under reduced pressure The residue is recrystallized from diisopropyl ether-hexane

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

Procedure: 1,3-Dimethoxy-5-ethylbenzene (7.69 g) is dissolved in acetic acid (80 ml), and thereto is added with stirring 47% hydrobromic acid at room temperature. The mixture is refluxed for three hours, and the reaction mixture is cooled to room temperature. The mixture is concentrated to dryness under reduced pressure, and the residue is dissolved in ethyl acetate. The organic layer is washed successively with water and a saturated aqueous sodium chloride solution, dried, and concentrated under reduced pressure. The residue is recrystallized from diisopropyl ether-hexane to give 1,3-dihydroxy-5-ethylbenzene (5.94 g), m.p. 97-98° C. is added The mixture is refluxed for three hours The mixture is concentrated to dryness under reduced pressure the residue is dissolved in ethyl acetate The organic layer is washed successively with water a saturated aqueous sodium chloride solution, dried concentrated under reduced pressure The residue is recrystallized from diisopropyl ether-hexane

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

Procedure: A mixture of 1.07 g (3.39 mmol) of 5-vinylresorcinol dibenzylether, as prepared in the preceding step, and 200 mg of 10% Pd/C in 20 mL of ethanol was hydrogenated at atmospheric pressure and ambient temperature for 14 h. The reaction mixture was filtered through diatomaceous earth (ethanol rinse) and concentrated to give 511 mg of the crude title compound which was used as is in the next reaction. 1H-NMR (300 MHz, CDCl3): δ 6 6.27 (dd, 1H, J=0.4, 2.2 Hz), 6.18 (t, 2H), 2.53 (q, 2H), 1.19 (t, 3H). Mass spectrum (MALDI-TOF; sinapinic acid matrix) calcd. for C8H10O2 :139.1 (M+H). Found: 139.5. The reaction mixture was filtered through diatomaceous earth (ethanol rinse) concentrated

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

Procedure: A mixture of 1.07 g (3.39 mmol) of 5-vinylresorcinol dibenzylether, as prepared in the preceding step, and 200 mg of 10% Pd/C in 20 mL of ethanol was hydrogenated at atmospheric pressure and ambient temperature for 14 h. The reaction mixture was filtered through diatomaceous earth (ethanol rinse) and concentrated to give 511 mg of the crude title compound which was used as is in the next reaction. 1H-NMR (300 MHz, CDCl3): δ 6 6.27 (dd, 1H, J=0.4, 2.2 Hz), 6.18 (t, 2H), 2.53 (q, 2H), 1.19 (t, 3H). Mass spectrum (MALDI-TOF; sinapinic acid matrix) calcd. for C8H10O2 :139.1 (M+H). Found: 139.5. The reaction mixture was filtered through diatomaceous earth (ethanol rinse) concentrated

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

Procedure: The title compound was prepared in 89% yield from 2-methylsulfonylbenzenesulfonyl chloride and 5-ethylresorcinol in a manner analogous to step a of Eg. 1. 1H-NMR (300 MHz, CDCl3) δ8.43 (d, J=7.8 Hz, 1H), 8.09 (d, J=7.8 Hz, 1H), 7.87 (t, J=7.8 Hz, 1H), 7.73 (t, J=7.7 Hz, 1H), 6.56 (s, 2H), 6.52 (s, 1H), 5.59 (br s, 1H), 3.45 (s, 3H), 2.49 (q, J=7.6 Hz, 2H), 1.09 (t, J=7.6 Hz, 3H).

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

Procedure: To a suspension of 5-ethyl-benzene-1,3-diol (2.17 g, 15.72 mmol) and triethyl orthoformate (23.26 g, 157 mmol) in benzene (40 mL) was added AlCl3 (6.30 g, 47.16 mmol) at 0° C. The reaction mixture was stirred at room temperature for 30 minutes. After cooling to room temperature, the mixture was poured onto ice and acidified with HCl. The mixture was extracted with EtOAc and the organic extracts was dried over anhydrous MgSO4 and concentrated in vacuo. The residue was purified by silica gel flash column chromatography to give 2-ethyl-4,6-dihydroxy-benzaldehyde (1.0 g, 38%). 1H NMR (400 MHz, CDCl3δ 12.40 (s, 1H), 10.08 (s, 1H), 6.25 (s, 1H), 6.00 (s, 1H), 5.80 (s, 1H), 2.90 (m, 2H), 1.30 (m, 3H). After cooling to room temperature the mixture was poured onto ice The mixture was extracted with EtOAc the organic extracts was dried over anhydrous MgSO4 concentrated in vacuo The residue was purified by silica gel flash column chromatography

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

Procedure: A mixture of 1-(3,5-dihydroxy-phenyl)-ethanone (5 g, 32.89 mmol), 10% Pd—C (1 g) in 4% HCl—H2O (100 mL) was hydrogenated at 1 atmosphere for 16 hours. The mixture was extracted with EtOAc and the organic extracts was dried over anhydrous MgSO4 and concentrated in vacuo. The residue was purified by silica gel flash column chromatography to give 5-ethyl-benzene-1,3-diol (2.37 g, 52%). 1H NMR (400 MHz, CDCl3δ 6.26 (s, 2H), 6.20 (s, 1H), 4.78 (s, 2H), 2.55 (m, 2H), 1.20 (m, 3H). The mixture was extracted with EtOAc the organic extracts was dried over anhydrous MgSO4 concentrated in vacuo The residue was purified by silica gel flash column chromatography

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

Procedure: 1,3-Dimethoxy-5-ethylbenzene (7.69 g) is dissolved in acetic acid (80 ml), and thereto is added with stirring 47% hydrobromic acid at room temperature. The mixture is refluxed for three hours, and the reaction mixture is cooled to room temperature. The mixture is concentrated to dryness under reduced pressure, and the residue is dissolved in ethyl acetate. The organic layer is washed successively with water and a saturated aqueous sodium chloride solution, dried, and concentrated under reduced pressure. The residue is recrystallized from diisopropyl ether-hexane to give 1,3-dihydroxy-5-ethylbenzene (5.94 g), m.p. 97-98° C. is added The mixture is refluxed for three hours The mixture is concentrated to dryness under reduced pressure the residue is dissolved in ethyl acetate The organic layer is washed successively with water a saturated aqueous sodium chloride solution, dried concentrated under reduced pressure The residue is recrystallized from diisopropyl ether-hexane

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

Procedure: A mixture of 1.07 g (3.39 mmol) of 5-vinylresorcinol dibenzylether, as prepared in the preceding step, and 200 mg of 10% Pd/C in 20 mL of ethanol was hydrogenated at atmospheric pressure and ambient temperature for 14 h. The reaction mixture was filtered through diatomaceous earth (ethanol rinse) and concentrated to give 511 mg of the crude title compound which was used as is in the next reaction. 1H-NMR (300 MHz, CDCl3): δ 6 6.27 (dd, 1H, J=0.4, 2.2 Hz), 6.18 (t, 2H), 2.53 (q, 2H), 1.19 (t, 3H). Mass spectrum (MALDI-TOF; sinapinic acid matrix) calcd. for C8H10O2 :139.1 (M+H). Found: 139.5. The reaction mixture was filtered through diatomaceous earth (ethanol rinse) concentrated