5-hydroxy-2-methylbenzaldehyde

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

Procedure: p-methoxybenzaldehyde; 2-hydroxy-p-tolualdehyde; 4-hydroxy-o-tolualdehyde; 6-hydroxy-m-tolualdehyde; and 4-hydroxy-m-tolualdehyde.

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

Procedure: 4-hydroxy-o-tolualdehyde; 6-hydroxy-m-tolualdehyde; and

Conditions: temp:170.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A stirred mixture of 5-methoxy-2-methylbenzaldehyde (24.9 g) and pyridine hydrochloride (100 g) is heated at 170° C. for 7 hours. Water (250 mL) is added cautiously to the reaction mixture at 140° C. and the very dark mixture is extracted twice with chloroform (250 mL), filtration through hyflo removes a small amount of insoluble black solid and aids separation. The organic phase is washed with 1 N hydrochloric acid (250 mL), with water (250 mL), with brine (250 mL), dried over magnesium sulphate and evaporated. The residue is washed with pentane to give 5-hydroxy-2-methylbenzaldehyde (10.66 g) as a cream solid, m.p. 116-118° C. the very dark mixture is extracted twice with chloroform (250 mL), filtration through hyflo removes a small amount of insoluble black solid and aids separation The organic phase is washed with 1 N hydrochloric acid (250 mL), with water (250 mL), with brine (250 mL) dried over magnesium sulphate evaporated The residue is washed with pentane

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

Procedure: 5-hydroxy-2-methylbenzaldehyde (3.4 g) is added portionwise to a stirred suspension of sodium hydride (1.2 g, 60% dispersion in mineral oil). The reaction mixture is stirred at room temperature for 45 minutes, 2-(trimethylsilyl)ethoxymethyl chloride (5 g) is added slowly and stirring continued for a further 3 hours. The mixture is evaporated and the residue partitioned between ethyl acetate (50 mL) and water (150 mL). The organic phase is washed with brine (150 mL) dried over magnesium sulphate and evaporated to give 2-methyl-5-(2-(trimethylsilyl)ethoxymethoxy)benzaldehyde (6.87 g) as a red-brown oil. stirring continued for a further 3 hours The mixture is evaporated the residue partitioned between ethyl acetate (50 mL) and water (150 mL) The organic phase is washed with brine (150 mL) dried over magnesium sulphate evaporated

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

Procedure: 4-hydroxy-o-tolualdehyde; 6-hydroxy-m-tolualdehyde; and

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

Procedure: p-methoxybenzaldehyde; 2-hydroxy-p-tolualdehyde; 4-hydroxy-o-tolualdehyde; 6-hydroxy-m-tolualdehyde; and 4-hydroxy-m-tolualdehyde.

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

Procedure: 4-hydroxy-o-tolualdehyde; 6-hydroxy-m-tolualdehyde; and

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

Procedure: 4-hydroxy-o-tolualdehyde; 6-hydroxy-m-tolualdehyde; and

Conditions: temp:170.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A stirred mixture of 5-methoxy-2-methylbenzaldehyde (24.9 g) and pyridine hydrochloride (100 g) is heated at 170° C. for 7 hours. Water (250 mL) is added cautiously to the reaction mixture at 140° C. and the very dark mixture is extracted twice with chloroform (250 mL), filtration through hyflo removes a small amount of insoluble black solid and aids separation. The organic phase is washed with 1 N hydrochloric acid (250 mL), with water (250 mL), with brine (250 mL), dried over magnesium sulphate and evaporated. The residue is washed with pentane to give 5-hydroxy-2-methylbenzaldehyde (10.66 g) as a cream solid, m.p. 116-118° C. the very dark mixture is extracted twice with chloroform (250 mL), filtration through hyflo removes a small amount of insoluble black solid and aids separation The organic phase is washed with 1 N hydrochloric acid (250 mL), with water (250 mL), with brine (250 mL) dried over magnesium sulphate evaporated The residue is washed with pentane

Conditions: temp:170.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A stirred mixture of 5-methoxy-2-methylbenzaldehyde (24.9 g) and pyridine hydrochloride (100 g) is heated at 170° C. for 7 hours. Water (250 mL) is added cautiously to the reaction mixture at 140° C. and the very dark mixture is extracted twice with chloroform (250 mL), filtration through hyflo removes a small amount of insoluble black solid and aids separation. The organic phase is washed with 1 N hydrochloric acid (250 mL), with water (250 mL), with brine (250 mL), dried over magnesium sulphate and evaporated. The residue is washed with pentane to give 5-hydroxy-2-methylbenzaldehyde (10.66 g) as a cream solid, m.p. 116-118° C. the very dark mixture is extracted twice with chloroform (250 mL), filtration through hyflo removes a small amount of insoluble black solid and aids separation The organic phase is washed with 1 N hydrochloric acid (250 mL), with water (250 mL), with brine (250 mL) dried over magnesium sulphate evaporated The residue is washed with pentane

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

Procedure: 5-hydroxy-2-methylbenzaldehyde (3.4 g) is added portionwise to a stirred suspension of sodium hydride (1.2 g, 60% dispersion in mineral oil). The reaction mixture is stirred at room temperature for 45 minutes, 2-(trimethylsilyl)ethoxymethyl chloride (5 g) is added slowly and stirring continued for a further 3 hours. The mixture is evaporated and the residue partitioned between ethyl acetate (50 mL) and water (150 mL). The organic phase is washed with brine (150 mL) dried over magnesium sulphate and evaporated to give 2-methyl-5-(2-(trimethylsilyl)ethoxymethoxy)benzaldehyde (6.87 g) as a red-brown oil. stirring continued for a further 3 hours The mixture is evaporated the residue partitioned between ethyl acetate (50 mL) and water (150 mL) The organic phase is washed with brine (150 mL) dried over magnesium sulphate evaporated

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

Procedure: 5-hydroxy-2-methylbenzaldehyde (3.4 g) is added portionwise to a stirred suspension of sodium hydride (1.2 g, 60% dispersion in mineral oil). The reaction mixture is stirred at room temperature for 45 minutes, 2-(trimethylsilyl)ethoxymethyl chloride (5 g) is added slowly and stirring continued for a further 3 hours. The mixture is evaporated and the residue partitioned between ethyl acetate (50 mL) and water (150 mL). The organic phase is washed with brine (150 mL) dried over magnesium sulphate and evaporated to give 2-methyl-5-(2-(trimethylsilyl)ethoxymethoxy)benzaldehyde (6.87 g) as a red-brown oil. stirring continued for a further 3 hours The mixture is evaporated the residue partitioned between ethyl acetate (50 mL) and water (150 mL) The organic phase is washed with brine (150 mL) dried over magnesium sulphate evaporated