2-(2-aminophenyl)propan-2-ol

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 15 g (0.1 mol) α,α-dimethyl-2-aminobenzyl alcohol and 5.7 g (0.1 mol) acetone in 120 ml of benzene was heated under reflux in a Dean-Stark trap for 3 hours. About 1.5 ml of water was separated from the reaction mixture. The benzene solution was then evaporated to give an oil which solidified on standing. Recrystallization from ethanol-water gave 5.2 g 2,2,4,4-tetramethyl-1,2-dihydro-4H-3,1-benzoxazine, as a white solid. under reflux in a Dean-Stark trap for 3 hours About 1.5 ml of water was separated from the reaction mixture The benzene solution was then evaporated to give an oil which Recrystallization from ethanol-water

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

Procedure: An 8.25-ml solution of 37% aqueous formaldehyde (0.099 mol) was added over 5 minutes to a cooled (0° C.) mixture of 10 g (0.066 mol) α,α-dimethyl-2-aminobenzyl alcohol in 50 ml water. The reaction mixture was then diluted with 50 ml benzene and vigorously stirred for 5 minutes. The aqueous layer was separated and extracted with benzene. The benzene layer of the reaction mixture and the benzene extracts were combined, dried over magnesium sulfate and evaporated. The resulting oil was distilled through a short column to give 6.3 g (b.p. 120° -125° C. at 0.1 mm of Hg) of 4,4-dimethyl-1,2-dihydro-4H-3,1-benzoxazine, as a colorless oil. Elemental analysis showed: %C, calc. 73.6, found 68.3: %H, calc. 8.0, found 7.6; %N, calc. 8.6, found 8.6. a cooled The aqueous layer was separated extracted with benzene dried over magnesium sulfate evaporated The resulting oil was distilled through a short column

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

Procedure: A solution of 15 g (0.1 mol) α,α-dimethyl-2-aminobenzyl alcohol and 5.7 g (0.1 mol) acetone in 120 ml of benzene was heated under reflux in a Dean-Stark trap for 3 hours. About 1.5 ml of water was separated from the reaction mixture. The benzene solution was then evaporated to give an oil which solidified on standing. Recrystallization from ethanol-water gave 5.2 g 2,2,4,4-tetramethyl-1,2-dihydro-4H-3,1-benzoxazine, as a white solid. under reflux in a Dean-Stark trap for 3 hours About 1.5 ml of water was separated from the reaction mixture The benzene solution was then evaporated to give an oil which Recrystallization from ethanol-water

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

Procedure: A 30.2-g (0.2 mol) sample of methyl 2-aminobenzoate in 150 ml diethyl ether was added dropwise to a solution of methyl magnesium iodide (prepared from 19.4 g of Mg and 127.8 g of methyl iodide) in 150 ml diethyl ether. The reaction mixture was then heated under reflux for 1 hour, cooled, and diluted with 200 ml of saturated aqueous ammonium chloride solution. The resulting aqueous mixture was extracted with ether. The ether extracts were dried over magnesium sulfate and evaporated to give 19.1 g of α,α-dimethyl-2-aminobenzyl alcohol. The reaction mixture was then heated under reflux for 1 hour cooled The resulting aqueous mixture was extracted with ether The ether extracts were dried over magnesium sulfate evaporated

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

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

Procedure: 112 g (1.13 mol) of phosgene are piped into 500 mL of THF. Then a solution of 52 g (0.34 mol) of 2-(2-aminophenyl)propan-2-ol, prepared from 2-aminoacetophenone and methylmagnesium iodide, in 300 mL of THF is added. The reaction mixture is left to stand overnight, evaporated down, and combined with 500 mL of pyridine. After the pyridine has been distilled off, water is added and the mixture is extracted with diethyl ether. The organic phases are washed successively with 2 N hydrochloric acid, sodium hydroxide solution and water, dried with sodium sulfate, and evaporated down. The residue remaining (46 g) is further reacted directly without any more purification. M.p. (toluene/petroleum ether)=109° C.-110° C. is added The reaction mixture is left evaporated down After the pyridine has been distilled off water is added the mixture is extracted with diethyl ether The organic phases are washed successively with 2 N hydrochloric acid, sodium hydroxide solution and water dried with sodium sulfate evaporated down is further reacted directly without any more purification

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

Procedure: 112 g (1.13 mol) of phosgene are piped into 500 mL of THF. Then a solution of 52 g (0.34 mol) of 2-(2-aminophenyl)propan-2-ol, prepared from 2-aminoacetophenone and methylmagnesium iodide, in 300 mL of THF is added. The reaction mixture is left to stand overnight, evaporated down, and combined with 500 mL of pyridine. After the pyridine has been distilled off, water is added and the mixture is extracted with diethyl ether. The organic phases are washed successively with 2 N hydrochloric acid, sodium hydroxide solution and water, dried with sodium sulfate, and evaporated down. The residue remaining (46 g) is further reacted directly without any more purification. M.p. (toluene/petroleum ether)=109° C.-110° C. is added The reaction mixture is left evaporated down After the pyridine has been distilled off water is added the mixture is extracted with diethyl ether The organic phases are washed successively with 2 N hydrochloric acid, sodium hydroxide solution and water dried with sodium sulfate evaporated down is further reacted directly without any more purification

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

Procedure: 112 g (1.13 mol) of phosgene are piped into 500 mL of THF. Then a solution of 52 g (0.34 mol) of 2-(2-aminophenyl)propan-2-ol, prepared from 2-aminoacetophenone and methylmagnesium iodide, in 300 mL of THF is added. The reaction mixture is left to stand overnight, evaporated down, and combined with 500 mL of pyridine. After the pyridine has been distilled off, water is added and the mixture is extracted with diethyl ether. The organic phases are washed successively with 2 N hydrochloric acid, sodium hydroxide solution and water, dried with sodium sulfate, and evaporated down. The residue remaining (46 g) is further reacted directly without any more purification. M.p. (toluene/petroleum ether)=109° C.-110° C. is added The reaction mixture is left evaporated down After the pyridine has been distilled off water is added the mixture is extracted with diethyl ether The organic phases are washed successively with 2 N hydrochloric acid, sodium hydroxide solution and water dried with sodium sulfate evaporated down is further reacted directly without any more purification

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

Procedure: Thus, for example, 4,4-dimethyl-6-isonicotinoylamino-7-nitro-4H-3,1-benzoxazin-2-one is obtained by reacting methyl anthranilate with methyl magnesium iodide in ethereal solution to obtain o-aminophenyl-dimethylcarbinol, which is cyclised by reacting with phosgene in a mixture of toluene and chloroform as solvent in the presence of solid potassium carbonate to obtain 4,4-dimethyl-4H-3,1-benzoxazin-2-one. By subsequent nitration with fuming nitric acid (d=1.52), 4,4-dimethyl-6-nitro-benzoxazin-2-one is obtained which is converted by catalytic hydrogenation in the presence of Raney nickel in dimethyl formamide into 6-amino-4,4-dimethyl-4H-3,1-benzoxazin-2-one. By inserting an acetyl protecting group by means of acetic anhydride, the precondition for further nitration with fuming nitric acid (d=1.52) is created in the 7- position of the molecule. The acetyl protecting group is split off again from the resulting 6-acetamido-4,4-dimethyl-7-nitro-4H-3,1-benzoxazin-2-on e by treating with concentrated hydrochloric acid in isopropanol, and the resulting 6-amino-4,4-dimethyl-7-nitro-4H-3,1-benzoxazin-2-one is converted into 4,4-dimethyl-6-isonicotinoylamido-7-nitro-4H-3,1-benzoxazin-2-one by treating with isonicotic acid chloride in pyridine as solvent.