341-58-2

Basic information

• Product Name: 2,2'-Bis(trifluoromethyl)benzidine
• Synonyms: 2,2'-Bis(trifluoroMethyl)-4,4'-diaMino biphenyl(TFMB/TFDB);2,2'-Bis(trifluoroMethyl)-4,4'-diaMino biphenyl (TFMB);2,2 '- (trifluoroMethyl) -4,4' - diaMino diphenyl;2,2'-Bis(trifluoromethyl)-[1,1'-biphenyl]-4,4'-diamine(TFDB/TFMB);ABL-21;4,4'-DIAMINO-2,2'-BIS(TRIFLUOROMETHYL)BIPHENYL;22TFMB;2,2'-DI(TRIFLUOROMETHYL)BENZIDINE
• CAS NO: 341-58-2
• Molecular Formula: C₁₄H₁₀F₆N₂
• Molecular Weight: 320.23
• EINECS: 1312995-182-4
• Product Categories: Biphenyls (for High-Performance Polymer Research);Functional Materials;Reagent for High-Performance Polymer Research;fine chemicals, specialty chemicals, intermediates, electronic chemical, organic synthesis;fine chemicals, specialty chemicals, intermediates, electronic chemical, organic synthesis, functional materials
• Mol File: 341-58-2.mol

Chemical Properties

• Melting Point: 183 °C
• Boiling Point: 376.9 °C at 760 mmHg
• Flash Point: 171.4 °C
• Appearance: white crystalline powder
• Density: 1.415 g/cm³
• Storage Temp.: 2-8°C(protect from light)
• Solubility: soluble in Methanol
• PKA: 3.23±0.10(Predicted)
• CAS DataBase Reference: 2,2'-Bis(trifluoromethyl)benzidine(CAS DataBase Reference)
• NIST Chemistry Reference: 2,2'-Bis(trifluoromethyl)benzidine(341-58-2)
• EPA Substance Registry System: 2,2'-Bis(trifluoromethyl)benzidine(341-58-2)

Safety Data

• Hazard Codes: T,Xi
• Statements: 22-45-50/53-36-25-36/37/38
• Safety Statements: 22-36/37/39-45-26-37
• RIDADR: 2811
• HazardClass: IRRITANT-HARMFUL
• Hazardous Substances Data: 341-58-2(Hazardous Substances Data)

Usage

Uses

2,2'-Bis(trifluoromethyl)benzidine is used for producing a high strength flexible transparent polyimide material.

Synthetic route

2,2'-bis-(trifluoromethyl)-4,4'-dinitro-1,1'-biphenyl (641-98-5) → 2,2'-bis(trifluoromethyl)benzidine (341-58-2)

Conditions	Yield
With ammonium formate; zinc In methanol at 50℃; Temperature; Concentration;	96.83%
With palladium 10% on activated carbon; hydrogen In ethanol at 80℃; under 15001.5 Torr; Catalytic behavior; Pressure; Temperature;	92%
With hydrogenchloride; tin
With hydrogen; palladium on activated charcoal In toluene at 60℃; under 7500.75 Torr; for 6h; Autoclave;

1,2-bis(3-(trifluoromethyl)phenyl)hydrazine (351-19-9) → 2,2'-bis(trifluoromethyl)benzidine (341-58-2)

Conditions	Yield
With sulfuric acid In water; toluene for 5h; Product distribution / selectivity;	95.1%
With hydrogenchloride In water; toluene at 25℃; for 3h; Product distribution / selectivity;	95%
With sulfuric acid In water at -5 - 75℃; under 2280.15 - 3800.26 Torr; for 2h; Temperature; Inert atmosphere;	60%

1,2-bis((3-trifluoromethyl)phenyl)diazene (588-00-1) → 2,2'-bis(trifluoromethyl)benzidine (341-58-2) + 4,2'-bis-trifluoromethyl-biphenyl-2,4'-diyldiamine (440-66-4)

Conditions	Yield
With sodium amalgam; ethanol; sulfuric acid

3-trifluoromethylnitrobenzene (98-46-4) → 2,2'-bis(trifluoromethyl)benzidine (341-58-2)

Conditions	Yield
Multi-step reaction with 2 steps 1: lead; sodium acetate; aqueous ethanol 2: sodium-amalgam; aqueous ethanol; H2SO4 View Scheme

N-[2-(trifluoromethyl)phenyl]acetamide (344-62-7) → 2,2'-bis(trifluoromethyl)benzidine (341-58-2)

Conditions	Yield
Multi-step reaction with 5 steps 1: H2SO4; HNO3 2: aq.-ethanolic NaOH 3: acetic acid; sulfuric acid; aqueous sodium nitrite solution; aqueous potassium iodide solution 4: copper-powder / 300 °C 5: tin; aq.-ethanolic HCl View Scheme

4-nitro-2-trifluoromethyl-aniline (121-01-7) → 2,2'-bis(trifluoromethyl)benzidine (341-58-2)

Conditions	Yield
Multi-step reaction with 3 steps 1: acetic acid; sulfuric acid; aqueous sodium nitrite solution; aqueous potassium iodide solution 2: copper-powder / 300 °C 3: tin; aq.-ethanolic HCl View Scheme

N-(4-nitro-2-(trifluoromethyl)phenyl)acetamide (395-68-6) → 2,2'-bis(trifluoromethyl)benzidine (341-58-2)

Conditions	Yield
Multi-step reaction with 4 steps 1: aq.-ethanolic NaOH 2: acetic acid; sulfuric acid; aqueous sodium nitrite solution; aqueous potassium iodide solution 3: copper-powder / 300 °C 4: tin; aq.-ethanolic HCl View Scheme

1-iodo-4-nitro-2-(trifluoromethyl)benzene (400-75-9) → 2,2'-bis(trifluoromethyl)benzidine (341-58-2)

Conditions	Yield
Multi-step reaction with 2 steps 1: copper-powder / 300 °C 2: tin; aq.-ethanolic HCl View Scheme

3,3'-bis (trifluoromethyl)-4,4'-hydrazobenzene + 3-trifluoromethylnitrobenzene (98-46-4) + zinc (7440-66-6) → 2,2'-bis(trifluoromethyl)benzidine (341-58-2)

Conditions	Yield
With sodium hydroxide; sulfuric acid; ammonium chloride; ammonia In methanol; acetone; toluene

C22H18F6N2O6 → 2,2'-bis(trifluoromethyl)benzidine (341-58-2)

Conditions	Yield
With water; sodium hydroxide In dichloromethane for 4h; Solvent; Reflux;	115 g

C24H22F6N2O6 → 2,2'-bis(trifluoromethyl)benzidine (341-58-2)

Conditions	Yield
With water; sodium hydroxide In dichloromethane for 4h; Reflux;	126.5 g

C26H26F6N2O6 → 2,2'-bis(trifluoromethyl)benzidine (341-58-2)

Conditions	Yield
With water; sodium hydroxide In dichloromethane for 4h; Reflux;	120.7 g

C22H14F6N2O6 → 2,2'-bis(trifluoromethyl)benzidine (341-58-2)

Conditions	Yield
With water; sodium hydroxide In dichloromethane for 4h; Reflux;	119.5 g

C30H18F6N2O6 → 2,2'-bis(trifluoromethyl)benzidine (341-58-2)

Conditions	Yield
With water; sodium hydroxide In dichloromethane for 4h; Reflux;	81.8 g

4-chloro-3-trifluoromethyl-aniline (320-51-4) → 2,2'-bis(trifluoromethyl)benzidine (341-58-2)

Conditions	Yield
Multi-step reaction with 3 steps 1.1: dichloromethane / 0 - 20 °C 2.1: sodium hydroxide / dichloromethane / 0.5 h / 20 °C 2.2: 5 h / 65 °C 3.1: water; sodium hydroxide / dichloromethane / 4 h / Reflux View Scheme

1-(tert-butoxycarbonyl)-L-proline (15761-39-4) + 2,2'-bis(trifluoromethyl)benzidine (341-58-2) → (2S,2'S)-di-tert-butyl 2,2'-(((2,2'-bis(trifluoromethyl)-[1,1'-biphenyl]-4,4'-diyl)bis(azanediyl))bis(carbonyl))bis(pyrrolidine-1-carboxylate)

Conditions	Yield
With N-(3-dimethylaminopropyl)-N-ethylcarbodiimide In dichloromethane at 20℃; for 2h;	96%
With 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride In dichloromethane at 20℃; for 2h;	96%

2,2'-bis(trifluoromethyl)benzidine (341-58-2) + 4-nitro-benzoyl chloride (122-04-3) → N,N'-(2,2'-bis(trifluoromethyl)-[1,1'-biphenyl]-4,4'-diyl)bis(4-nitrobenzamide)

Conditions	Yield
With pyridine In tetrahydrofuran Cooling with ice;	95.7%
With pyridine In N,N-dimethyl acetamide at 80℃; for 3h;	65.4%

2,2'-bis(trifluoromethyl)benzidine (341-58-2) + 4-chlorobenzaldehyde (104-88-1) → (N4Z,N4'Z)-N4,N4'-bis(4-chlorobenzylidene)-2,2'-bis(trifluoromethyl)biphenyl-4,4'-diamine

Conditions	Yield
In ethanol at 20℃; for 3h; Reflux;	94.15%

2,2'-bis(trifluoromethyl)benzidine (341-58-2) + MeCOX → 4,4'-Diacetylamino-2,2'-bis(trifluoromethyl)biphenyl

Conditions	Yield
	94%

2,2'-bis(trifluoromethyl)benzidine (341-58-2) + 4-hydroxy-benzaldehyde (123-08-0) → 4,4'-(1Z,1'Z)-(2,2'-bis(trifluoromethyl)biphenyl-4,4'-diyl)bis(azan-1-yl-1-ylidene)bis(methan-1-yl-1-ylidene)diphenol

Conditions	Yield
In ethanol at 20℃; for 3h; Reflux;	93.35%

4-chlorophthalic anhydride (118-45-6) + 2,2'-bis(trifluoromethyl)benzidine (341-58-2) → C30H12Cl2F6N2O4

Conditions	Yield
With 4-hydroxymethyl-1,3-dioxolan-2-one at 180℃; for 14h;	91.8%

pyridine-2-carbaldehyde (1121-60-4) + Diethyl phosphonate (762-04-9, 123-22-8) + 2,2'-bis(trifluoromethyl)benzidine (341-58-2) → tetraethyl (2,2'-bis(trifluoromethyl)biphenyl-4,4'-diyl)bis(azanediyl)bis(pyridin-2-ylmethylene)diphosphonate

Conditions	Yield
With water at 45℃; for 0.5h; Sonication; Green chemistry;	91.76%

Diethyl phosphonate (762-04-9, 123-22-8) + 2,2'-bis(trifluoromethyl)benzidine (341-58-2) + 4-fluorobenzaldehyde (459-57-4) → tetraethyl (2,2'-bis(trifluoromethyl)biphenyl-4,4'-diyl)bis(azanediyl)bis((4-fluorophenyl)methylene)diphosphonate

Conditions	Yield
With water at 45℃; for 0.5h; Sonication; Green chemistry;	91.42%

Diethyl phosphonate (762-04-9, 123-22-8) + 2,2'-bis(trifluoromethyl)benzidine (341-58-2) + 3-nitro-benzaldehyde (99-61-6) → tetraethyl (2,2'-bis(trifluoromethyl)biphenyl-4,4'-diyl)bis(azanediyl)bis((3-nitrophenyl)methylene)diphosphonate

Conditions	Yield
With water at 45℃; for 0.5h; Reagent/catalyst; Temperature; Time; Sonication; Green chemistry;	91.07%

Diethyl phosphonate (762-04-9, 123-22-8) + 2,2'-bis(trifluoromethyl)benzidine (341-58-2) + 4-chlorobenzaldehyde (104-88-1) → tetraethyl (2,2'-bis(trifluoromethyl)biphenyl-4,4'-diyl)bis(azanediyl)bis((4-chlorophenyl)methylene)diphosphonate

Conditions	Yield
With water at 45℃; for 0.5h; Sonication; Green chemistry;	90.46%

Diethyl phosphonate (762-04-9, 123-22-8) + 2,2'-bis(trifluoromethyl)benzidine (341-58-2) + 4-ethylbenzylaldehyde (4748-78-1) → tetraethyl (2,2'-bis(trifluoromethyl)biphenyl-4,4'-diyl)bis(azanediyl)bis((4-ethylphenyl)methylene)diphosphonate

Conditions	Yield
With water at 45℃; for 0.5h; Sonication; Green chemistry;	90.35%

Diethyl phosphonate (762-04-9, 123-22-8) + 2,2'-bis(trifluoromethyl)benzidine (341-58-2) + benzaldehyde (100-52-7) → tetraethyl (2,2'-bis(trifluoromethyl)biphenyl-4,4'-diyl)bis(azanediyl)bis(phenylmethylene)diphosphonate

Conditions	Yield
With water at 45℃; for 0.5h; Sonication; Green chemistry;	89.91%

Diethyl phosphonate (762-04-9, 123-22-8) + 2,2'-bis(trifluoromethyl)benzidine (341-58-2) + 4-dimethylamino-benzaldehyde (100-10-7) → tetraethyl (2,2'-bis(trifluoromethyl)biphenyl-4,4'-diyl)bis(azanediyl)bis((4-(dimethylamino)phenyl)methylene)diphosphonate

Conditions	Yield
With water at 45℃; for 0.5h; Sonication; Green chemistry;	89.17%

Diethyl phosphonate (762-04-9, 123-22-8) + 2,2'-bis(trifluoromethyl)benzidine (341-58-2) + 4-hydroxy-benzaldehyde (123-08-0) → tetraethyl (2,2'-bis(trifluoromethyl)biphenyl-4,4'-diyl)bis(azanediyl)bis((4-hydroxyphenyl)methylene)diphosphonate

Conditions	Yield
With water at 45℃; for 0.5h; Sonication; Green chemistry;	88.23%

thiophene-2-carbaldehyde (98-03-3) + Diethyl phosphonate (762-04-9, 123-22-8) + 2,2'-bis(trifluoromethyl)benzidine (341-58-2) → tetraethyl (2,2'-bis(trifluoromethyl)biphenyl-4,4'-diyl)bis(azanediyl)bis(thiophen-2-ylmethylene)diphosphonate

Conditions	Yield
With water at 45℃; for 0.5h; Sonication; Green chemistry;	87.79%

Diethyl phosphonate (762-04-9, 123-22-8) + 2,2'-bis(trifluoromethyl)benzidine (341-58-2) + 4-methoxy-benzaldehyde (123-11-5) → tetraethyl (2,2'-bis(trifluoromethyl)biphenyl-4,4'-diyl)bis(azanediyl)bis((4-methoxyphenyl)methylene)diphosphonate

Conditions	Yield
With water at 45℃; for 0.5h; Sonication; Green chemistry;	86.68%

2,2'-bis(trifluoromethyl)benzidine (341-58-2) → 4,4'-Dibromo-2,2'-bis(trifluoromethyl)biphenyl

Conditions	Yield
Stage #1: 2,2'-bis(trifluoromethyl)benzidine With sulfuric acid; sodium nitrite In water at 2 - 65℃; for 1h; Stage #2: With hydrogen bromide; copper(I) bromide at 45℃; Reagent/catalyst;	86%
With tert.-butylnitrite; copper(ll) bromide	60%

4-nitrophthalic anhydride (5466-84-2) + 2,2'-bis(trifluoromethyl)benzidine (341-58-2) → C30H12F6N4O8

Conditions	Yield
With propionic acid at 150℃; for 10h;	80%

2,2'-bis(trifluoromethyl)benzidine (341-58-2) + C19H8F6O7 → C52H18F18N2O10

Conditions	Yield
Stage #1: 2,2'-bis(trifluoromethyl)benzidine; C19H8F6O7 In 1-methyl-pyrrolidin-2-one at 90℃; for 1h; Stage #2: With pyridine; acetic anhydride In 1-methyl-pyrrolidin-2-one at 90℃; for 2h; Temperature;	80%

2,2'-bis(trifluoromethyl)benzidine (341-58-2) → 2,2'-bis(trifluoromethyl)-4,4'-diiodobiphenyl (89803-70-3)

Conditions	Yield
Stage #1: 2,2'-bis(trifluoromethyl)benzidine With sulfuric acid; sodium nitrite In water; acetic acid at 5℃; for 1h; Stage #2: With potassium iodide In water for 3h;	78.4%
Stage #1: 2,2'-bis(trifluoromethyl)benzidine With hydrogenchloride; sodium nitrite In water at 0 - 5℃; Stage #2: With iodine; sodium iodide In dichloromethane; water at 5 - 20℃;	75%
With sodium iodide; sulfuric acid; iodine; sodium hydrogensulfite; sodium nitrite In dichloromethane; water	13.3 grams (78%)
Stage #1: 2,2'-bis(trifluoromethyl)benzidine With sulfuric acid; sodium nitrite Stage #2: With iodine; sodium iodide Further stages.;

2,2'-bis(trifluoromethyl)benzidine (341-58-2) + 3-methyl-4-nitro-benzoyl chloride (35675-46-8) → C30H20F6N4O6

Conditions	Yield
With pyridine In tetrahydrofuran at 20℃; for 12h; Sealed tube; Cooling with ice;	76%

2,2'-bis(trifluoromethyl)benzidine (341-58-2) → 2,2′-bis(trifluoromethyl)-4,4′-dihydroxybiphenyl

Conditions	Yield
With uranyl nitrate hydrate; water; trifluoroacetic acid for 96h; Irradiation; Inert atmosphere;	75%
Stage #1: 2,2'-bis(trifluoromethyl)benzidine With hydrogenchloride; sodium nitrite In water at -4℃; for 2h; Inert atmosphere; Stage #2: With phosphoric acid In water at 20℃; for 25h; Inert atmosphere; Reflux;	46.9%
Stage #1: 2,2'-bis(trifluoromethyl)benzidine With methanesulfonic acid In water Stage #2: With sodium nitrite In water at 10 - 20℃; for 12h; Stage #3: With sulfuric acid; water at 120℃;

2,2'-bis(trifluoromethyl)benzidine (341-58-2) → 3,3',5,5'-tetrabromo-2,2'-bis(trifluoromethyl)-[1,1'-biphenyl]-4,4'-diamine

Conditions	Yield
With bromine In methanol at 20℃; for 14h; Reflux;	75%

2,2'-bis(trifluoromethyl)benzidine (341-58-2) + pyromellitic acid monoanhydride (7487-10-7) → C34H10F6N2O10

Conditions	Yield
Stage #1: 2,2'-bis(trifluoromethyl)benzidine; pyromellitic acid monoanhydride In 1-methyl-pyrrolidin-2-one; N,N-dimethyl acetamide at 90℃; for 1h; Stage #2: With pyridine; acetic anhydride In 1-methyl-pyrrolidin-2-one; N,N-dimethyl acetamide; toluene at 90℃;	72%
Stage #1: 2,2'-bis(trifluoromethyl)benzidine; pyromellitic acid monoanhydride In 1-methyl-pyrrolidin-2-one at 90℃; for 1h; Stage #2: With pyridine; acetic anhydride In 1-methyl-pyrrolidin-2-one at 90℃; for 2h;

4-hydroxyphthalic anhydride (27550-59-0) + 2,2'-bis(trifluoromethyl)benzidine (341-58-2) → C30H14F6N2O6

Conditions	Yield
With propionic acid at 150℃; for 10h;	70%

2,2'-bis(trifluoromethyl)benzidine (341-58-2) + trimellitic Anhydride (552-30-7) → 2,2'-bis(trifluoromethyl)-4,4'-bis(trimelletimide)biphenyl

Conditions	Yield
With acetic acid Reflux;	56.1%

2,2'-bis(trifluoromethyl)benzidine (341-58-2) + trifluoroacetic anhydride (407-25-0) → 4,4'-bis-(trifluoroacetamido)-2,2'-bis(trifluoromethyl)-5,5'-dinitrobiphenyl

Conditions	Yield
With potassium nitrate at 5 - 10℃; for 72h;	51%

Upstream product

• 641-98-5 2,2'-bis-(trifluoromethyl)-4,4'-dinitro-1,1'-biphenyl 
• 588-00-1 1,2-bis(3-(trifluoromethyl)phenyl)diazene 
• 98-46-4 3-trifluoromethylnitrobenzene 
• 344-62-7 N-[2-(trifluoromethyl)phenyl]acetamide 
• 121-01-7 4-nitro-2-trifluoromethyl-aniline 
• 395-68-6 N-(4-nitro-2-(trifluoromethyl)phenyl)acetamide 
• 400-75-9 1-iodo-4-nitro-2-(trifluoromethyl)benzene 
• 351-19-9 1,2-bis(3-(trifluoromethyl)phenyl)hydrazine 
• 7440-66-6 zinc 
• 320-51-4 4-chloro-3-trifluoromethyl-aniline 
• 88-16-4 1-chloro-2-(trifluoromethyl)benzene 
• 87-69-4 L-Tartaric acid 

Downstream Products

• 89803-70-3 2,2'-bis(trifluoromethyl)-4,4'-diiodobiphenyl 
• 89803-71-4 2,2′-bis-trifluoromethyl-biphenyl-4,4′-dicarboxylic acid 

Relevant articles and documents

Homocoupling of a Grignard Reagent toward the Synthesis of 2,2′-Bis(trifluoromethyl)-4,4′-diaminobiphenyl

A new process for the synthesis of 2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl (TFMB) comprising three steps has been industrially developed. The first step is the homocoupling of the Grignard reagent derived from 1-chloro-2-(trifluoromethyl)benzene with iron chloride(III) in the presence of an oxidizing agent to afford 2,2′-bis(trifluoromethyl)biphenyl. The second step is the nitration of this biphenyl to 2,2′-bis(trifluoromethyl)-4,4′-dinitrobiphenyl, and the third step is the reduction of this dinitrobiphenyl using hydrogen over Pd/C to afford TFMB. This process has been demonstrated on an industrial scale.

METHOD OF MANUFACTURING BIS(TRIFLUOROMEHTYL)DIAMINOBIPHENYL COMPOUND

To exemplary embodiments of the present invention, a bis dinitrobiphenyl compound is prepared. On the solution the bis dinitrobiphenyl based compound is reacted with an alkali sulfide. The productivity of bis diaminobiphenyl compounds can be improved.

Synthesis method of 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl

The invention discloses a synthesis method of 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl. The method comprises the following steps: subjecting 2-chloro-5-aminobenzotrifluoride serving as a starting raw material and acyclic anhydride in a formula I to amidation to obtain an intermediate II, then carrying out reductive coupling reaction on the intermediate II to obtain an intermediate III, and finally carrying out deamidation reaction on the intermediate III to obtain the 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, wherein the cyclic anhydride in the formula I is succinic anhydride, glutaric anhydride, adipic anhydride or maleic anhydride. The starting material 2-chloro-5-aminobenzotrifluoride is an important farm chemical and medical intermediate, and is low in price, convenient and easy to obtain; the synthesis route is short, the reaction condition is mild, and the method is environment-friendly; the total yield of the synthetic route can reach 60-80%, and compared with the prior art, the synthetic route has obvious advantages and is suitable for industrial mass production.

Preparation method of 2,2'-bis (trifluoromethyl)-4,4'-diaminobiphenyl

The invention discloses a preparation method of 2,2'-bis (trifluoromethyl)-4,4'-diaminobiphenyl. The method comprises the following steps: S1, preparing 3,3'-bis (trifluoromethyl) diphenylhydrazine through catalytic reduction reaction by taking m-nitrobenzotrifluoride and hydrazine hydrate as raw materials and taking low-boiling-point alcohol as a solvent under the catalysis of inorganic base and palladium carbon at 40-76 DEG C; and S2, in a protective gas atmosphere, adding the 3,3'-bis (trifluoromethyl) diphenylhydrazine prepared in the step S1 into inorganic acid, and preparing 2,2'-bis (trifluoromethyl)-4,4'-diaminobiphenyl through a rearrangement reaction at a temperature of -10 DEG C to 20 DEG C. According to the invention, hydrazine hydrate is used as a reducing agent instead of hydrogen, the use amount of the hydrazine hydrate is small, the reaction condition is mild, the requirement on equipment is low, and the catalyst is small in use amount, reusable and low in cost.

Preparation Method for 2,2'-Bis(Trifluoromethyl)-4,4'-Diaminobiphenyl

The present invention relates to a method for producing 3,3 '- bis 2,2 - diaminobiphenyl by a benzidine rearrangement reaction from' -4 bis hydrazinobenzene in high yield, and more specifically, to dissolve 4 3,3 '-' - bis hydrazinobenzene in (A) organic solvent. (B) The solution prepared in (A) is added dropwise to an inorganic acid solution while maintaining a temperature below 0 °C.30°C. When the (C) titration is completed, less than 0 °C -30°C or less is reacted. 2,2 '- Bis -4, 4' - diaminobiphenyl, which is characterized in that it comprises.

Method for preparing polyimide monomer having low yellow index

The present invention chemically synthesizes a polyimide monomer. 10. The synthesized polyimide monomer is introduced into the loading area of the sublimation purification apparatus. - 3 TTTorr under vacuum above sublimation temperature of the synthesized polyimide monomer, followed by recrystallization. Provided is a method for preparing a polyimide monomer having improved yellowness index.

DIAMINE COMPOUND, POLYIMIDE PRECURSOR AND POLYIMIDE FILM PREPARED BY USING SAME

The present invention discloses a novel diamine having a structure including an intramolecular imide group while having an aromatic ring group with a rigid structure. In addition, and by comprising the novel diamine as a polymerization component, the present invention can provide a polyimide film having improved mechanical and thermal properties while maintaining optical properties of polyimide.

Preparation method of 2,2'-bis(trifluoromethyl)-4,4'-biphenyldiamine

The invention belongs to the technical field of organic synthesis, and particularly relates to a preparation method of 2,2'-bis(trifluoromethyl)-4,4'-biphenyldiamine. The preparation method comprisesthe following steps of coupled reaction: in a polar aprotic solvent, under the catalysis effect of a main catalyst and a cocatalyst and the activation effect of ligands, 2-bromine-5-nitrobenzotrifluoride takes coupled reaction to generate 2,2'-bis(trifluoromethyl)-4,4'-dinitrobipheny; (2) hydrogenation reaction: the 2,2'-bis(trifluoromethyl)-4,4'-dinitrobipheny prepared in the first step, catalysts and solvents are mixed, and react with hydrogen gas in a microchannel for hydrogenation reaction; the 2,2'-bis(trifluoromethyl)-4,4'-biphenyldiamine is obtained. The preparation method has the advantages that the operation is simple; the catalyst consumption is little; the reaction energy consumption is low; the yield and the purity of the product are improved; the method is applicable to continuous production.

Preparation method of 2,2'-bis(trifluoromethyl)-4,4'-diaminodiphenyl

The invention relates to a preparation method of 2,2'-bis(trifluoromethyl)-4,4'-diaminodiphenyl. The preparation method comprises the following steps: synthesizing 3,3'-bis(trifluoromethyl)hydrazo-benzene in an inorganic alkaline aqueous solution by adopting nitrobenzotrifluoride as a raw material, adopting a phase transfer catalyst, a co-catalyst and Pd/C as a catalytic system and adopting aromatic hydrocarbon as a solvent, and performing the re-arrangement reaction on the 3,3'-bis(trifluoromethyl)hydrazo-benzene in an inorganic acid aqueous solution, thus obtaining 2,2'-bis(trifluoromethyl)-4,4'-diaminodiphenyl, wherein the phase transfer catalyst is one or a mixture of more of sodium dodecyl benzene sulfonate, sodium dodecyl sulfate and cetyl trimethyl ammonium bromide, and the co-catalyst is one or a mixture of more of 2,3-dichloro-1,4-naphthoquinone, 2-hydroxyanthraquinone and 2,6-dioxyanthraquinone. The preparation method has the advantages of mild reaction condition, simple process, high product quality and yield, low production cost, environmental friendliness, suitability for continuous production and the like.

Preparation method of 2,2'-bis-trifluoromethyl-4,4'-diaminodiphenyl

The invention relates to a preparation method of 2,2'-bis-trifluoromethyl-4,4'-diaminodiphenyl. The preparation method includes the steps that 2,2'-bis-trifluoromethyl-4,4'-diaminodiphenyl is dissolved in polar proton solvent methyl alcohol, reducing agent anhydrous ammonium formate and catalyst zinc powder are added, the temperature is raised to 30-50 DEG C for a reaction till the raw material 2,2'-bis-trifluoromethyl-4,4'-diaminodiphenyl completely reacts, heat filtration is conducted, a filter cake is washed with methyl alcohol, filter liquor is decompressed, the solvent is recovered, after crystals are separated out, cooling and filtering are conducted, and off-white crystals, namely, 2,2'-bis-trifluoromethyl-4,4'-diaminodiphenyl are obtained. According to 2,2'-bis-trifluoromethyl-4,4'-diaminodiphenyl, the ratio of anhydrous ammonium formate to the zinc powder to methyl alcohol is 1:(4-8):(0.1-0.2):(30-40). Ammonium formate is adopted for reducing, the zinc powder is adopted as the catalyst, and the advantages of being high in reaction yield, mild in condition, low in cost, simple in after-treatment, environmentally friendly and the like are achieved.