CN104262166B - A kind of preparation method of o-phenylenediamine and its derivatives - Google Patents

Abstract

The present invention specifically relates to a method for synthesizing organic compounds. In order to solve the problems in the current method for synthesizing o-phenylenediamine derivatives, such as complex process routes, many by-products that are difficult to purify, harsh reaction conditions, and serious environmental pollution, the present invention proposes an ortho-phenylenediamine derivative. The preparation method of phenylenediamine and its derivatives uses azobenzene and its derivatives as raw materials, synthesizes o-nitroazobenzene and its derivatives through the joint action of catalysts, oxidants, and nitrating agents, and then reduces them to o-nitroazobenzene and its derivatives by reducing reagents. The synthesis method of the phenylenediamine and its derivatives has the advantages of cheap and easy-to-obtain raw materials, simple and safe operation, short synthesis steps, simple purification, and no large amount of waste acid pollution.

Description

A kind of preparation method of o-phenylenediamine and its derivatives

technical field

The invention specifically relates to a method for synthesizing organic compounds, in particular to a method for preparing o-phenylenediamine using azobenzene as a raw material, which is first nitrated and then reduced.

Background technique

O-phenylenediamine derivatives are an important class of organic synthesis and fine chemical intermediates, mainly used in the production of benzimidazole fungicides, such as the prevention and treatment of bacterial diseases of various crops, trees, fruits and vegetables, as well as the preservation and storage of fruits and vegetables Carbendazim and thiophanate-methyl, etc. In addition, o-phenylenediamine derivatives are used as dye intermediates for the preparation of vat dyes and cationic dyes, and the production of fur yellow brown M, cationic dyes, vat red GG, vat brilliant Orange Gr. It is also used in the manufacture of polyamide, polyurethane and leveling agent.

At present, the domestic production of o-phenylenediamine mainly includes three methods: alkali sulfide reduction and catalytic hydrogenation reduction. The reaction at ~110°C can also be carried out at a reaction temperature of 120~130°C and normal pressure, and the reaction time is 3~4 hours to obtain o-phenylenediamine; (2) iron powder reduction is to use o-nitroaniline to reduce iron powder Under the action of o-phenylenediamine. Although these two methods have simple production techniques, the product yield is low and the cost is high. In particular, a large amount of waste water generated is difficult to handle and the environmental pollution is quite serious. (3) Process for preparing o-phenylenediamine by catalytic hydrogenation, such as Chinese patent CN102633653A, which discloses a method for preparing o-phenylenediamine by catalytic hydrogenation of o-nitroaniline, although it has good product quality and high yield , "three wastes" and other advantages, but usually need to operate under high pressure conditions, high requirements for equipment and safety. In addition, the raw material o-nitroaniline used in the above method is obtained by nitration of aniline after acetylation and then mixed acid nitration and then hydrolysis. Restricted by the rules, multiple isomers will appear in the nitration step in the synthesis of raw materials, which are difficult to separate.

Therefore, it is very necessary to develop a novel, general-purpose, easy-to-operate and short-step synthesis method for o-phenylenediamine.

Contents of the invention

In order to solve the problems in the current method for synthesizing o-phenylenediamine and its derivatives such as complex process route, many by-products that are difficult to purify, harsh reaction conditions and serious environmental pollution, the present invention proposes a method for producing o-phenylenediamine and its derivatives The preparation method, the synthesis method of the present invention has the advantages of cheap and easy-to-obtain raw materials, simple and safe operation, short synthesis steps, simple purification, no large amount of waste acid pollution, and the like.

The present invention is achieved through the following technical scheme: a preparation method of o-phenylenediamine and its derivatives is to use azobenzene and its derivatives as raw materials, and synthesize o-nitroazo through the joint action of catalyst, oxidizing agent and nitrating agent Benzene and its derivatives are then reduced to o-phenylenediamine and its derivatives by a reducing agent. The reaction structure is as follows:

,

R in the reaction structural formula is selected from one of H, methyl, ethyl, methoxy, isopropyl, tert-butyl, phenyl, nitrile, nitro, or halogen.

The specific steps are: adding azobenzene and its derivatives, catalysts, oxidizing agents, and nitrating agents into a pressure-resistant sealed tube of an organic solvent to react; after the reaction is completed, filter to remove the filter residue, wash the filter residue with dichloromethane, collect the filtrate and dry; Then the solvent in the filtrate is spin-dried, purified with a silica gel column, and the eluent is eluted to obtain o-nitroazobenzene and its derivatives; Under ambient conditions, the reduction reaction at room temperature is carried out for 10 to 30 hours to obtain the final product o-phenylenediamine and its derivatives.

Described catalyst is selected from one in palladium acetate, palladium chloride, triphenylphosphine palladium chloride, tetrakis (triphenylphosphine) palladium, diacetonitrile palladium dichloride, and the catalyst and azobenzene and its derivatives The molar ratio is 1:5~10, preferably 1:10.

The oxidizing agent is selected from one of potassium persulfate, iodobenzene diacetate, and cerium ammonium nitrate (CAN), and the molar ratio of the oxidizing agent to azobenzene and its derivatives is 1~3:1, preferably 2 :1.

The nitrating reagent is selected from sodium nitrite, potassium nitrite, and silver nitrite, and the molar ratio to azobenzene and its derivatives is 1-3:1, preferably 2:1.

The organic solvent for the reaction is a low-polarity organic solvent, preferably 1,2-dichloroethane (DEC), and the amount used is the amount to dissolve the solvent.

The reaction temperature is 80-130°C, and the reaction time is 24-72 hours, and the reaction is preferably 110°C, 24 hours.

The eluent is a mixed solution of ethyl acetate and petroleum ether, wherein the volume ratio of ethyl acetate to petroleum ether is 1:6.

The reducing agent is a mixed reagent of zinc powder and formic acid in methanol solvent. The concentration of o-nitroazobenzene in formic acid is 0.1~0.2N, the molar ratio of zinc powder to o-nitroazobenzene and its derivatives is 1~1.5:1,

Preferably, the reduction reaction time is 24 hours. The inert gas is preferably nitrogen or argon, and the room temperature is 20-25 degrees Celsius.

Compared with prior art, the beneficial effect of the present invention is:

(1) The raw material azobenzene is directly synthesized from aniline, without going through the complicated steps of aniline to acetanilide, nitration and reduction to finally obtain o-nitroaniline, and the route is simple;

(2) No isomers are produced in the nitration step of azobenzene, which avoids complicated isomer separation steps;

(3) No excessive nitration products are produced in the azobenzene nitration step, avoiding waste acid pollution;

(4) The reduction from o-nitroazobenzene to o-phenylenediamine requires only one step, and the equipment requirements are not high.

detailed description

The present invention will be described in further detail below by way of examples.

Example 1:

Add 54.6 mg (0.3 mmol) azobenzene, 6.7 mg (0.03 mmol) palladium acetate, 92.3 mg (0.6 mmol) silver nitrite, 162.2 mg (0.6 mmol) potassium persulfate, 3.5 mL DCE into a closed reaction vessel , the reaction mixture was stirred and reacted at 110° C. for 72 hours. After the reaction stopped, cool to room temperature, add 10 mL of dichloromethane to the reaction solution, remove the solvent after suction filtration under reduced pressure, and the residue was subjected to column chromatography [GF254 silica gel (100-200 mesh); eluent was V (petroleum ether)/V(ethyl acetate)=6/1] separation and purification to obtain reddish-brown solid 2-nitroazobenzene with a yield of 95%. 2-Nitroazobenzene (0.3 mmol), zinc powder (0.36 mmol), and formic acid (2 mL) were mixed and reacted in methanol solvent under nitrogen atmosphere for 24 hours at room temperature to obtain o-benzene with a yield of 88%. diamine.

mp 102-104 ºC; IR (neat): n = 3352 (NH2) cm ^-1 ; 1H NMR (CDCl3, 500MHz): δ 6.76-6.72 (m, 4H), 3.38 (s, 4H); 13C NMR (CDCl3 , 125 MHz): δ 134.76,120.28, 116.76; GC-MS (EI, 70 eV): m/z = 108 [M+].

Example 2:

Add 54.6 mg (0.3 mmol) of azobenzene, 0.03 mmol of palladium chloride, 0.6 mmol of potassium nitrite, 0.6 mmol of ceric ammonium nitrate, 3.5 mL of DCE into a closed reaction vessel, and stir the reaction mixture at 110°C for 48 Hour. After the reaction stopped, cool to room temperature, add 10 mL of dichloromethane to the reaction solution, remove the solvent after suction filtration under reduced pressure, and the residue was subjected to column chromatography [GF254 silica gel (100-200 mesh); eluent was V (petroleum ether)/V(ethyl acetate)=6/1] separation and purification to obtain reddish-brown solid 2-nitroazobenzene with a yield of 70%. 2-Nitroazobenzene (0.3 mmol), zinc powder (0.45 mol), and formic acid (3 mL) were mixed and reacted in a methanol solvent under nitrogen at room temperature for 24 hours to obtain o-benzene with a yield of 80%. diamine.

mp 102-104 ºC; IR (neat): n = 3352 (NH2) cm ^-1 ; 1H NMR (CDCl3, 500MHz): δ 6.76-6.72 (m, 4H), 3.38 (s, 4H); 13C NMR (CDCl3 , 125 MHz): δ 134.76,120.28, 116.76; GC-MS (EI, 70 eV): m/z = 108 [M+].

Example 3:

Add 0.3 mmol of azobenzene, 0.03 mmol of diacetonitrile palladium dichloride, 0.6 mmol of sodium nitrite, 0.6 mmol of potassium persulfate, 3.5 mL of DCE into a closed reaction vessel, and stir the reaction mixture at 110°C for 72 hours . After the reaction stopped, cool to room temperature, add 10 mL of dichloromethane to the reaction solution, remove the solvent after suction filtration under reduced pressure, and the residue was subjected to column chromatography [GF254 silica gel (100-200 mesh); eluent was V (petroleum ether)/V(ethyl acetate)=6/1] separation and purification to obtain reddish-brown solid 2-nitroazobenzene with a yield of 56%. 2-Nitroazobenzene (0.3 mmol), zinc powder (0.36 mol), and formic acid (2 mL) were mixed and reacted in methanol solvent under nitrogen at room temperature for 24 hours to obtain o-benzene with a yield of 88%. diamine.

mp 102-104 ºC; IR (neat): n = 3352 (NH2) cm ^-1 ; 1H NMR (CDCl3, 500MHz): δ 6.76-6.72 (m, 4H), 3.38 (s, 4H); 13C NMR (CDCl3 , 125 MHz): δ 134.76,120.28, 116.76; GC-MS (EI, 70 eV): m/z = 108 [M+].

Example 4

0.3 mmol of azobenzene, 0.06 mmol of palladium acetate, 0.6 mmol of silver nitrite, 0.6 mmol of potassium persulfate, and 3.5 mL of DCE were added into a closed reaction vessel, and the reaction mixture was stirred at 90°C for 48 hours. After the reaction stopped, cool to room temperature, add 10 mL of dichloromethane to the reaction solution, remove the solvent after suction filtration under reduced pressure, and the residue was subjected to column chromatography [GF254 silica gel (100-200 mesh); eluent was V (petroleum Ether)/V (ethyl acetate)=6/1] separation and purification, obtain reddish-brown solid 2-nitroazobenzene, productive rate is 85%. 2-Nitroazobenzene (0.3 mmol), zinc powder (0.36 mol), and formic acid (1.5 mL) were mixed and reacted in a methanol solvent under argon at room temperature for 24 hours, and the yield of 80% was obtained. phenylenediamine.

mp 102-104 ºC; IR (neat): n = 3352 (NH2) cm ^-1 ; 1H NMR (CDCl3, 500MHz): δ 6.76-6.72 (m, 4H), 3.38 (s, 4H); 13C NMR (CDCl3 , 125 MHz): δ 134.76,120.28, 116.76; GC-MS (EI, 70 eV): m/z = 108 [M+].

Example 5

0.3 mmol of azobenzene, 0.08 mmol of palladium chloride, 0.3 mmol of silver nitrite, 0.3 mmol of ceric ammonium nitrate, and 3.5 mL of DCE were added into a closed reaction vessel, and the reaction mixture was stirred at 80°C for 72 hours. After the reaction stopped, cool to room temperature, add 10 mL of dichloromethane to the reaction solution, remove the solvent after suction filtration under reduced pressure, and the residue was subjected to column chromatography [GF254 silica gel (100-200 mesh); eluent was V (petroleum ether)/V(ethyl acetate)=6/1] separation and purification to obtain reddish-brown solid 2-nitroazobenzene with a yield of 54%. 2-Nitroazobenzene (0.3 mmol), zinc powder (0.45 mol), and formic acid (2 mL) were mixed and reacted in methanol solvent at room temperature under nitrogen for 30 hours, and the yield of phthalate was 85%. amine.

mp 102-104 ºC; IR (neat): n = 3352 (NH2) cm ^-1 ; 1H NMR (CDCl3, 500MHz): δ 6.76-6.72 (m, 4H), 3.38 (s, 4H); 13C NMR (CDCl3 , 125 MHz): δ 134.76,120.28, 116.76; GC-MS (EI, 70 eV): m/z = 108 [M+].

Embodiment 6:

In a closed reaction vessel, add 0.3 mmol 4,4'-dimethylazobenzene, 0.03 mmol triphenylphosphine palladium chloride, 0.9 mmol potassium nitrite, 0.9 mmol potassium persulfate, 3.5 mL DCE, and the reaction mixture The reaction was stirred at 130°C for 36 hours. After the reaction stopped, cool to room temperature, add 10 mL of dichloromethane to the reaction solution, remove the solvent after suction filtration under reduced pressure, and the residue was subjected to column chromatography [GF254 silica gel (100-200 mesh); eluent was V (petroleum ether)/V(ethyl acetate)=6/1] separation and purification to obtain reddish-brown solid 2-nitro-4,4'-dimethylazobenzene with a yield of 65%. Mix 2-nitro-4,4'-dimethylazobenzene (0.3 mmol), zinc powder (0.45 mol), and formic acid (3 mL), and react in methanol solvent under nitrogen at room temperature for 10 hours to obtain A yellow solid of 4-methyl-1,2-phenylenediamine was obtained with a yield of 76%.

mp 87-89 ºC; IR (neat): ( = 3422 (NH ₂ ) cm ^-1 ; ¹ H NMR (CDCl ₃ , 500 MHz): δ6.63 (d, J = 10 Hz, 1H), 6.54 (t , J = 5 Hz, 2H), 3.30 (s, 4H), 2.23 (s, 3H); ¹³ C NMR (CDCl ₃ , 125 MHz): δ 134.99, 131.82, 129.97, 117.40, 117.05, 20.66; GC-MS (EI, 70 eV): m/z = 122 [M ⁺ ].

Embodiment 7:

Add 0.3 mmol 2,2'-dimethylazobenzene, 0.03 mmol palladium acetate, 0.9 mmol sodium nitrite, 0.9 mmol iodobenzene diacetate, 3.5 mL DCE to a closed reaction vessel, and the reaction mixture is heated at 110°C The reaction was stirred for 72 hours. After the reaction stopped, cool to room temperature, add 10 mL of dichloromethane to the reaction solution, remove the solvent after suction filtration under reduced pressure, and the residue was subjected to column chromatography [GF254 silica gel (100-200 mesh); eluent was V (petroleum ether)/V(ethyl acetate)=6/1] separation and purification to obtain brown liquid 2-nitro-6,6'-dimethylazobenzene with a yield of 69%. Mix 2-nitro-6,6'-dimethylazobenzene (0.3 mmol), zinc powder (0.36 mol), and formic acid (2 mL), and react in methanol solvent under nitrogen at room temperature for 20 hours to obtain A yellow solid of 2-methyl-1,2-phenylenediamine was obtained with a yield of 89%.

mp 71-72 ºC; IR (neat): ( = 3413 (NH ₂ ) cm ^-1 ; ¹ H NMR (CDCl ₃ , 500 MHz): δ6.58 (d, J = 10 Hz, 1H), 6.52 (t , J = 5 Hz, 2H), 3.41 (s, 4H), 2.26 (s, 3H); ¹³ C NMR (CDCl ₃ , 125 MHz): δ 135.11, 132.82, 129.13, 116.40, 116.05, 19.74; GC-MS (EI, 70 eV): m/z = 122 [M ⁺ ].

Embodiment 8:

Add 0.3 mmol 3,3'-dimethylazobenzene, 0.05 mmol tetrakis(triphenylphosphine) palladium, 0.6 mmol silver nitrite, 0.6 mmol cerium ammonium nitrate, 3.5 mL DCE to a closed reaction vessel, and react The mixture was stirred and reacted at 90° C. for 60 hours. After the reaction stopped, cool to room temperature, add 10 mL of dichloromethane to the reaction solution, remove the solvent after suction filtration under reduced pressure, and the residue was subjected to column chromatography [GF254 silica gel (100-200 mesh); eluent was V (petroleum ether)/V(ethyl acetate)=6/1] separation and purification to obtain brown liquid 2-nitro-5,5'-dimethylazobenzene with a yield of 90%. Mix 2-nitro-5,5'-dimethylazobenzene (0.3 mmol), zinc powder (0.45 mol), and formic acid (1.5 mL), and react in methanol solvent under nitrogen at room temperature for 24 hours to obtain A yellow solid of 4-methyl-1,2-phenylenediamine was obtained with a yield of 90%.

mp 87-89 ºC; IR (neat): ( = 3422 (NH ₂ ) cm ^-1 ; ¹ H NMR (CDCl ₃ , 500 MHz): δ6.63 (d, J = 10 Hz, 1H), 6.54 (t , J = 5 Hz, 2H), 3.30 (s, 4H), 2.23 (s, 3H); ¹³ C NMR (CDCl ₃ , 125 MHz): δ 134.99, 131.82, 129.97, 117.40, 117.05, 20.66; GC-MS (EI, 70 eV): m/z = 122 [M ⁺ ].

Embodiment 9:

In a closed reaction vessel, add 0.3 mmol 3,3',5,5'-tetramethylazobenzene, 0.06 mmol palladium acetate, 0.5 mmol potassium nitrite, 0.5 mmol potassium persulfate, 3.5 mL DCE, the reaction mixture The reaction was stirred at 100°C for 50 hours. After the reaction stopped, cool to room temperature, add 10 mL of dichloromethane to the reaction solution, remove the solvent after suction filtration under reduced pressure, and the residue was subjected to column chromatography [GF254 silica gel (100-200 mesh); eluent was V (petroleum ether)/V(ethyl acetate)=6/1] separation and purification to obtain brown liquid 2-nitro-3,3',5,5'-tetramethylazobenzene with a yield of 63%. Mix 2-nitro3,3',5,5'-tetramethylazobenzene (0.3 mmol), zinc powder (0.36mol), formic acid (3 mL), and react in methanol solvent under nitrogen at room temperature After 24 hours, a yellow solid of 3,5-dimethyl-1,2-phenylenediamine was obtained with a yield of 75%.

mp 127-128 ºC; IR (neat): ( = 3456 (NH ₂ ) cm ^-1 ; ¹ H NMR (CDCl ₃ , 500 MHz): δ 6.53 (s, 1H), 6.48 (d, J = 10 Hz, 1H), 3.06 (s, 4H), 2.20 (t, J = 10 Hz,3H), 2.14 (s, 3H); ¹³ C NMR (CDCl ₃ , 125 MHz): δ 134.22, 132.31, 130.55, 128.71,122.54 , 118.57, 20.57, 18.85; GC-MS (EI, 70 eV): m/z = 136 [M ⁺ ].

Example 10:

Add 0.3 mmol 3,3',4,4'-tetramethylazobenzene, 0.03 mmol tetrakis(triphenylphosphine) palladium, 0.6 mmol sodium nitrite, 0.6 mmol iodobenzene diacetate in a closed reaction vessel , 3.5 mL of DCE, and the reaction mixture was stirred at 110°C for 40 hours. After the reaction stopped, cool to room temperature, add 10 mL of dichloromethane to the reaction solution, remove the solvent after suction filtration under reduced pressure, and the residue was subjected to column chromatography [GF254 silica gel (100-200 mesh); eluent was V (petroleum ether)/V(ethyl acetate)=6/1] separation and purification to obtain brown liquid 2-nitro-3,3'4,4'-tetramethylazobenzene with a yield of 74%. Mix 2-nitro-3,3',4,4'-tetramethylazobenzene (0.3 mmol), zinc powder (0.36 mol), formic acid (2 mL) in a methanol solvent under nitrogen at room temperature After reacting for 24 hours, a yellow solid of 4,5-dimethyl-1,2-phenylenediamine was obtained with a yield of 78%.

mp 126-128 ºC; IR (neat): ( = 3451 (NH ₂ ) cm ^-1 ; ¹ H NMR (CDCl ₃ , 500 MHz): δ 6.48 (d, J = 10 Hz, 2H), 3.21 (s, 4H), 2.20 (d, J = 10 Hz, 6H); ¹³ C NMR(CDCl ₃ , 125 MHz): δ 134.24, 130.56, 128.70, 123.58, 122.53, 115.61, 20.57,17.39; GC-MS (EI, 70 eV): m/z = 136 [M ⁺ ].

Claims (3)

1. an o-phenylenediamine and the preparation method of derivant thereof, it is characterised in that described preparation method be with diphenyl diimide and Its derivant is raw material, jointly acts on the adjacent nitro-azo benzene and its derivative of synthesis through catalyst, oxidant, nitrating agent, then Being reduced to o-phenylenediamine and derivant thereof by going back original reagent, reaction structure formula is as follows:

R in reaction structure formula is selected from H, methyl, ethyl, methoxyl group, isopropyl, the tert-butyl group, phenyl, itrile group, nitro or halogen In one,

Described concretely comprises the following steps: azobenzene and its derivatives, catalyst, oxidant, nitrating agent are joined organic solvent Pressure-resistant seal pipe reacts；After having reacted, it is filtered to remove filtering residue, and washs filtering residue with dichloromethane, collect filtrate and be dried；So After the solvent in filtrate is spin-dried for, be purified with silicagel column, eluent obtains adjacent nitro-azo benzene and its derivative；Again will Gained neighbour nitro-azo benzene derivative with go back original reagent, in an inert atmosphere, room temperature reduction reaction 10 ~ 30 hours, obtain End-product o-phenylenediamine and derivant thereof,

Described original reagent of going back is zinc powder, the formic acid mix reagent in methanol solvate, dense in formic acid of adjacent nitroazobenzene Degree is 0.1 ~ 0.2N, and zinc powder is 1 ~ 1.5: 1 with the mol ratio of adjacent nitro-azo benzene and its derivative；

Described catalyst is selected from palladium, Palladous chloride., triphenylphosphine palladium chloride, tetrakis triphenylphosphine palladium, diacetonitrile dichloride Mol ratio 1:5 ~ 10 of one, catalyst and azobenzene and its derivatives in palladium；

Described oxidant one in potassium peroxydisulfate, iodobenzene diacetate, the ammonium ceric nitrate, oxidant and diphenyl diimide and spread out Biological mol ratio is 1 ~ 3:1；

Described nitrating agent is selected from sodium nitrite, and potassium nitrite, the one in silver nitrite, with azobenzene and its derivatives Mol ratio is 1 ~ 3:1.

A kind of o-phenylenediamine the most according to claim 1 and the preparation method of derivant thereof, it is characterised in that: described reaction Organic solvent be 1,2-dichloroethanes.

A kind of o-phenylenediamine the most according to claim 1 and the preparation method of derivant thereof, it is characterised in that in resistance to densification In tube sealing, reaction temperature is 80 ~ 130 DEG C, and the response time is 24 ~ 72 hours.