2,2-dichloro-1-(3-methyl-2,3-dihydro-1,4-benzoxazin-4-yl)ethanone

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

Procedure: 5.3 ml (55 mmoles) of dichloroacetyl chloride are added dropwise, at a temperature of 20° to 25° C. and while stirring, to a suspension of 7.5 g (50 mmoles) of 2,3-dihydro-3-methyl-1,4-benzoxazine and 5.8 g (55 mmoles) of sodium carbonate in 120 ml of benzene. The reaction mixture is then stirred at the same temperature for 30 minutes and is then taken up in a mixture of water and ethyl acetate. The organic phase is washed with saturated sodium chloride solution, dried over sodium sulfate and evaporated. Crystallising the residue from diisopropyl ether gives 10.8 g of 4-dichloroacetyl-2,3-dihydro-3-methyl-1,4-benzoxazine, melting point 105°-107° C. The organic phase is washed with saturated sodium chloride solution dried over sodium sulfate evaporated Crystallising the residue from diisopropyl ether

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

Procedure: 5.3 ml (55 mmoles) of dichloroacetyl chloride are added dropwise, at a temperature of 20° to 25° C. and while stirring, to a suspension of 7.5 g (50 mmoles) of 2,3-dihydro-3-methyl-1,4-benzoxazine and 5.8 g (55 mmoles) of sodium carbonate in 120 ml of benzene. The reaction mixture is then stirred at the same temperature for 30 minutes and is then taken up in a mixture of water and ethyl acetate. The organic phase is washed with saturated sodium chloride solution, dried over sodium sulfate and evaporated. Crystallising the residue from diisopropyl ether gives 10.8 g of 4-dichloroacetyl-2,3-dihydro-3-methyl-1,4-benzoxazine, melting point 105°-107° C. The organic phase is washed with saturated sodium chloride solution dried over sodium sulfate evaporated Crystallising the residue from diisopropyl ether

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

Procedure: 5.3 ml (55 mmoles) of dichloroacetyl chloride are added dropwise, at a temperature of 20° to 25° C. and while stirring, to a suspension of 7.5 g (50 mmoles) of 2,3-dihydro-3-methyl-1,4-benzoxazine and 5.8 g (55 mmoles) of sodium carbonate in 120 ml of benzene. The reaction mixture is then stirred at the same temperature for 30 minutes and is then taken up in a mixture of water and ethyl acetate. The organic phase is washed with saturated sodium chloride solution, dried over sodium sulfate and evaporated. Crystallising the residue from diisopropyl ether gives 10.8 g of 4-dichloroacetyl-2,3-dihydro-3-methyl-1,4-benzoxazine, melting point 105°-107° C. The organic phase is washed with saturated sodium chloride solution dried over sodium sulfate evaporated Crystallising the residue from diisopropyl ether

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

Procedure: 5.3 ml (55 mmoles) of dichloroacetyl chloride are added dropwise, at a temperature of 20° to 25° C. and while stirring, to a suspension of 7.5 g (50 mmoles) of 2,3-dihydro-3-methyl-1,4-benzoxazine and 5.8 g (55 mmoles) of sodium carbonate in 120 ml of benzene. The reaction mixture is then stirred at the same temperature for 30 minutes and is then taken up in a mixture of water and ethyl acetate. The organic phase is washed with saturated sodium chloride solution, dried over sodium sulfate and evaporated. Crystallising the residue from diisopropyl ether gives 10.8 g of 4-dichloroacetyl-2,3-dihydro-3-methyl-1,4-benzoxazine, melting point 105°-107° C. The organic phase is washed with saturated sodium chloride solution dried over sodium sulfate evaporated Crystallising the residue from diisopropyl ether

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

Procedure: The preparation of benoxacor, a safener in the use of herbicides, is a three-stage process: in the first stage, o-nitrophenol is reacted with chloroacetone to give o-nitrophenoxyacetone; in the second stage, the compound is hydrogenated so as to obtain a benzoxazine, which is then acylated. This process is described in EP1283829.

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

Procedure: 5.3 ml (55 mmoles) of dichloroacetyl chloride are added dropwise, at a temperature of 20° to 25° C. and while stirring, to a suspension of 7.5 g (50 mmoles) of 2,3-dihydro-3-methyl-1,4-benzoxazine and 5.8 g (55 mmoles) of sodium carbonate in 120 ml of benzene. The reaction mixture is then stirred at the same temperature for 30 minutes and is then taken up in a mixture of water and ethyl acetate. The organic phase is washed with saturated sodium chloride solution, dried over sodium sulfate and evaporated. Crystallising the residue from diisopropyl ether gives 10.8 g of 4-dichloroacetyl-2,3-dihydro-3-methyl-1,4-benzoxazine, melting point 105°-107° C. The organic phase is washed with saturated sodium chloride solution dried over sodium sulfate evaporated Crystallising the residue from diisopropyl ether