Preparation method of 4'-chloro-2-nitrobiphenyl

Abstract

The invention discloses a preparation method of 4'-chloro-2-nitrobiphenyl. 4'-chloro-2-nitrobiphenyl is obtained by reaction of p-chlorophenyl magnesium halide and 2-nitro-halogenobenzene in a solvent in the presence of a nickel catalyst. The preparation method provided by the invention has the advantages of no need of using an expensive palladium catalyst, low cost, few reaction steps, high reaction selectivity and high yield.

Description

technical field

[0001] The present invention relates to a kind of preparation method of 4'-chloro-2-nitrobiphenyl. Background technique

[0002] 4'-chloro-2-nitrobiphenyl is an important intermediate of the pesticide boscalid, and its preparation method has the following reports in the prior art:

[0003] Chinese patent CN97192942.4 discloses a method for preparing 4'-chloro-2-nitrobiphenyl: taking p-chlorophenylboronic acid or its alkyl ester, acid anhydride and o-chloronitrobenzene as raw materials, in the presence of a palladium catalyst Suzuki coupling reaction occurs under the action of 4'-chloro-2-nitrobiphenyl. Chinese patent CN200680006706.2 improves the above method by using bis(4-chlorophenyl)boronic acid instead of p-chlorophenylboronic acid for coupling reaction, which reduces the expensive alkylboronic acid used in the preparation of p-chlorophenylboronic acid The consumption of ester and improved reactivity to reduce the consumption of palladium catalyst. Th...

Examples

Embodiment 1

[0025] Dissolve 10.0g of 2-nitrochlorobenzene in 180mL of tetrahydrofuran, add 3.4g of 1,2-bis(diphenylphosphine)ethane nickel chloride, cool down to -45°C, and keep the system temperature at -40°C~-45°C Slowly add 98.7g of 11% tetrahydrofuran solution of p-chlorophenylmagnesium chloride in about 2 hours, keep it warm for 6 hours after dropping, remove the cold source, slowly rise to room temperature, add 30mL of toluene and 30mL of 20% hydrochloric acid, stir, and static layer Finally, the organic layer was evaporated to dryness to obtain a crude oil product, which was recrystallized using isopropanol to obtain 11.4 g of a yellow solid. After testing, the obtained yellow solid was 4'-chloro-2-nitrobiphenyl with a purity of 96.3%. The reaction yield is 74%.

Embodiment 2

[0027] Dissolve 10.0g of 2-nitroiodobenzene in 150mL of tetrahydrofuran, add 2.3g of 1,2-bis(diphenylphosphine)ethane nickel chloride, cool down to -78°C, and keep the system temperature at -78°C~-70°C Slowly add 45.7g of 15% tetrahydrofuran solution of p-chlorophenylmagnesium chloride in about 4 hours, keep it warm for 12 hours after dropping, remove the cold source, slowly rise to room temperature, add 30mL of toluene and 30mL of 20% hydrochloric acid, stir and statically separate Finally, the organic layer was evaporated to dryness to obtain a crude oil product, which was recrystallized using isopropanol to obtain 6.36 g of a yellow solid. After testing, the obtained yellow solid was 4'-chloro-2-nitrobiphenyl with a purity of 97.0%. The reaction yield is 66%.

Embodiment 3

[0029] Dissolve 10.0 g of 2-nitrochlorobenzene in 200 mL of tetrahydrofuran, add 6.8 g of 1,2-bis(diphenylphosphine)ethane nickel chloride, cool down to -50°C, and keep the system temperature at -45°C~-50°C Slowly add 108.5g of 10% tetrahydrofuran solution of p-chlorophenylmagnesium chloride in about 3 hours, keep it warm for 4 hours after dropping, remove the cold source, slowly rise to room temperature, add 30mL of toluene and 30mL of 20% hydrochloric acid, stir and statically separate Finally, the organic layer was evaporated to dryness to obtain a crude oil product, which was recrystallized using isopropanol to obtain 11.9 g of a light yellow solid. After testing, the obtained yellow solid was 4'-chloro-2-nitrobiphenyl with a purity of 97.5%. The reaction yield is 78%.

technical field

[0001] The present invention relates to a kind of preparation method of 4'-chloro-2-nitrobiphenyl. Background technique

[0002] 4'-chloro-2-nitrobiphenyl is an important intermediate of the pesticide boscalid, and its preparation method has the following reports in the prior art:

[0003] Chinese patent CN97192942.4 discloses a method for preparing 4'-chloro-2-nitrobiphenyl: taking p-chlorophenylboronic acid or its alkyl ester, acid anhydride and o-chloronitrobenzene as raw materials, in the presence of a palladium catalyst Suzuki coupling reaction occurs under the action of 4'-chloro-2-nitrobiphenyl. Chinese patent CN200680006706.2 improves the above method by using bis(4-chlorophenyl)boronic acid instead of p-chlorophenylboronic acid for coupling reaction, which reduces the expensive alkylboronic acid used in the preparation of p-chlorophenylboronic acid The consumption of ester and improved reactivity to reduce the consumption of palladium catalyst. Th...

Examples

Embodiment 1

[0025] Dissolve 10.0g of 2-nitrochlorobenzene in 180mL of tetrahydrofuran, add 3.4g of 1,2-bis(diphenylphosphine)ethane nickel chloride, cool down to -45°C, and keep the system temperature at -40°C~-45°C Slowly add 98.7g of 11% tetrahydrofuran solution of p-chlorophenylmagnesium chloride in about 2 hours, keep it warm for 6 hours after dropping, remove the cold source, slowly rise to room temperature, add 30mL of toluene and 30mL of 20% hydrochloric acid, stir, and static layer Finally, the organic layer was evaporated to dryness to obtain a crude oil product, which was recrystallized using isopropanol to obtain 11.4 g of a yellow solid. After testing, the obtained yellow solid was 4'-chloro-2-nitrobiphenyl with a purity of 96.3%. The reaction yield is 74%.

Embodiment 2

[0027] Dissolve 10.0g of 2-nitroiodobenzene in 150mL of tetrahydrofuran, add 2.3g of 1,2-bis(diphenylphosphine)ethane nickel chloride, cool down to -78°C, and keep the system temperature at -78°C~-70°C Slowly add 45.7g of 15% tetrahydrofuran solution of p-chlorophenylmagnesium chloride in about 4 hours, keep it warm for 12 hours after dropping, remove the cold source, slowly rise to room temperature, add 30mL of toluene and 30mL of 20% hydrochloric acid, stir and statically separate Finally, the organic layer was evaporated to dryness to obtain a crude oil product, which was recrystallized using isopropanol to obtain 6.36 g of a yellow solid. After testing, the obtained yellow solid was 4'-chloro-2-nitrobiphenyl with a purity of 97.0%. The reaction yield is 66%.

Embodiment 3

[0029] Dissolve 10.0 g of 2-nitrochlorobenzene in 200 mL of tetrahydrofuran, add 6.8 g of 1,2-bis(diphenylphosphine)ethane nickel chloride, cool down to -50°C, and keep the system temperature at -45°C~-50°C Slowly add 108.5g of 10% tetrahydrofuran solution of p-chlorophenylmagnesium chloride in about 3 hours, keep it warm for 4 hours after dropping, remove the cold source, slowly rise to room temperature, add 30mL of toluene and 30mL of 20% hydrochloric acid, stir and statically separate Finally, the organic layer was evaporated to dryness to obtain a crude oil product, which was recrystallized using isopropanol to obtain 11.9 g of a light yellow solid. After testing, the obtained yellow solid was 4'-chloro-2-nitrobiphenyl with a purity of 97.5%. The reaction yield is 78%.

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