6-hydroxy-2,2-dimethyl-3H-chromen-4-one

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:

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

Procedure: A solution of 50 g (0.26 mol) of 2,2-dimethyl-6-hydroxychroman-4-one (Example 28a) in 500 ml of DMF was added dropwise to a suspension of 9.0 g (0.3 mol) of 80% sodium hydride in 500 ml of DMF. After stirring at RT for 90 min, 49 g (0.265 mol) of iodobutane were added and the mixture was stirred at RT for a further 90 min. The reaction mixture was then concentrated in vacuo, the residue was treated with water and the mixture was extracted several times with EA. The organic phases were washed with 5 M sodium hydroxide solution, stirred with activated carbon and magnesium sulfate, filtered and concentrated. 57.6 g of 6-butoxy-2,2-dimethylchroman-4-one were obtained. the mixture was stirred at RT for a further 90 min The reaction mixture was then concentrated in vacuo the residue was treated with water the mixture was extracted several times with EA The organic phases were washed with 5 M sodium hydroxide solution stirred with activated carbon and magnesium sulfate filtered concentrated

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

Procedure: 25.2 g (131.2 mmol) of 6-hydroxy-2,2-dimethylchroman-4-one were introduced into 350 ml of diethyl ketone with stirring at RT and, after addition of 18.0 g (131 mmol) of powdered potassium carbonate, the mixture was stirred at 75° C. for 30 min. After cooling to 60° C., 15.7 ml (131 mmol) of benzyl bromide were added dropwise, and after 2 h the mixture was concentrated in vacuo, the residue was treated with water and the solid was filtered off with suction, 37 g, m.p. 105-107° C. the mixture was stirred at 75° C. for 30 min After cooling to 60° C. after 2 h the mixture was concentrated in vacuo the residue was treated with water the solid was filtered off with suction, 37 g, m.p. 105-107° C.

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

Procedure: A solution of 50 g (0.26 mol) of 2,2-dimethyl-6-hydroxychroman-4-one (Example 1a) in 500 ml of DMF was added dropwise to a suspension of 9.0 g (0.3 mol) of 80 percent sodium hydride in 500 ml of DMF. The mixture was stirred at RT for 90 min, 49 g (0.265 mol) of iodobutane were added and the mixture was stirred at RT for a further 90 min. The reaction mixture was then concentrated under reduced pressure and the residue was admixed with water and extracted repeatedly with EA. The organic phases were washed with 5 M aqueous sodium hydroxide solution, stirred with activated carbon and magnesium sulfate, filtered and concentrated. This procedure gave 57.6 g of 6-butoxy-2,2-dimethylchroman-4-one. the mixture was stirred at RT for a further 90 min The reaction mixture was then concentrated under reduced pressure extracted repeatedly with EA The organic phases were washed with 5 M aqueous sodium hydroxide solution stirred with activated carbon and magnesium sulfate filtered concentrated

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

Procedure: A solution of 50 g (0.26 mol) of 2,2-dimethyl-6-hydroxychroman-4-one (Example 1a) in 500 ml of DMF was added dropwise to a suspension of 9.0 g (0.3 mol) of 80 percent sodium hydride in 500 ml of DMF. The mixture was stirred at RT for 90 min, 49 g (0.265 mol) of iodobutane were added and the mixture was stirred at RT for a further 90 min. The reaction mixture was then concentrated under reduced pressure and the residue was admixed with water and extracted repeatedly with EA. The organic phases were washed with 5 M aqueous sodium hydroxide solution, stirred with activated carbon and magnesium sulfate, filtered and concentrated. This procedure gave 57.6 g of 6-butoxy-2,2-dimethylchroman-4-one. the mixture was stirred at RT for a further 90 min The reaction mixture was then concentrated under reduced pressure extracted repeatedly with EA The organic phases were washed with 5 M aqueous sodium hydroxide solution stirred with activated carbon and magnesium sulfate filtered concentrated

Conditions: temp:75.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: At RT, 25.2 g (131.2 mmol) of 6-hydroxy-2,2-dimethylchroman-4-one were introduced with stirring into 350 ml of diethyl ketone and, after addition of 18.0 g (131 mmol) of powdered potassium carbonate, stirred at 75° C. for 30 min. After cooling to 60° C., 15.7 ml (131 mmol) of benzyl bromide were added dropwise, and after 2 h the mixure was concentrated i. vac., the residue was treated with water and the solid was filtered off with suction, 37 g, m.p. 109-110° C. After cooling to 60° C. after 2 h the mixure was concentrated i , the residue was treated with water the solid was filtered off with suction, 37 g, m.p. 109-110° C.

Conditions: temp:45.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A reaction mixture of 100 g (0.65 mol) of 2,5-dihydroxyacetophenone in 1 l of acetonitrile, 130 ml (1.55 mol) of pyrrolidine and 290 ml (3.95 mol) of acetone was heated at 45° C. for 8 h. The sol. were then removed i. vac. and the residue was dissolved in 1 l of EA. The organic phase was washed twice with dilute hydrochloric acid, stirred with activated carbon and dried over magnesium sulfate and substantially concentrated. The residue was stirred with petroleum ether and the precipitate was filtered off with suction giving 102 g of 2,2-dimethyl-6-hydroxychroman-4-one, m.p. 161° C. The sol. were then removed i and the residue was dissolved in 1 l of EA The organic phase was washed twice with dilute hydrochloric acid dried over magnesium sulfate substantially concentrated The residue was stirred with petroleum ether the precipitate was filtered off with suction

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

Procedure: 25.2 g (131.2 mmol) of 6-hydroxy-2,2-dimethylchroman-4-one were introduced into 350 ml of diethyl ketone with stirring at RT and, after addition of 18.0 g (131 mmol) of powdered potassium carbonate, stirred at 75° C. for 30 min. After cooling to 60° C., 15.7 ml (131 mmol) of benzyl bromide were added dropwise, the mixture was concentrated in vac. after 2 h, the residue was treated with water and the solid was filtered off with suction, 37 g, m.p. 105-107° C. stirred at 75° C. for 30 min After cooling to 60° C. the mixture was concentrated in vac the residue was treated with water the solid was filtered off with suction, 37 g, m.p. 105-107° C.

Conditions: temp:45.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A reaction mixture of 100 g (0.65 mol) of 2,5-dihydroxyacetophenone in 1 l of acetonitrile, 130 ml (1.55 mol) of pyrrolidine and 290 ml (3.95 mol) of acetone was heated to 45° C. for 8 h. The solvents were then stripped off in vac. and the residue was dissolved in 1 l of EA. The organic phase was washed twice with dilute hydrochloric acid, stirred with activated carbon and dried over magnesium sulfate and largely concentrated. After stirring the residue with petroleum ether and filtering off the precipitate with suction, 102 g of 2,2-dimethyl-6-hydroxychroman-4-one, m.p. 158° C., were obtained. The organic phase was washed twice with dilute hydrochloric acid dried over magnesium sulfate largely concentrated After stirring the residue with petroleum ether filtering off the precipitate with suction, 102 g of 2,2-dimethyl-6-hydroxychroman-4-one, m.p. 158° C. were obtained