616-82-0

Basic information

• Product Name: 4-Hydroxy-3-nitrobenzoic acid
• Synonyms: NHB;RARECHEM AL BO 1164;4-HYDROXY-3-NITROBENZOIC ACID;3-NITRO-4-HYDROXYBENZOIC ACID;2-NITRO-4-CYANOPHENOL;LABOTEST-BB LT00452849;3,4-Nitrohydroxybenzoic acid;Benzoic acid, 4-hydroxy-3-nitro-
• CAS NO: 616-82-0
• Molecular Formula: C₇H₅NO₅
• Molecular Weight: 183.12
• EINECS: 210-494-1
• Product Categories: Aromatic Carboxylic Acids, Amides, Anilides, Anhydrides & Salts;Organic acids;C7;Carbonyl Compounds;Carboxylic Acids
• Mol File: 616-82-0.mol
• Article Data: 33

Chemical Properties

• Melting Point: 183-186 °C(lit.)
• Boiling Point: 316.77°C (rough estimate)
• Flash Point: 162.528 °C
• Appearance: yellow to light brown powder
• Density: 1.6074 (rough estimate)
• Vapor Pressure: 1.24E-05mmHg at 25°C
• Refractive Index: 1.6280 (estimate)
• Storage Temp.: -20°C
• Solubility: Acetonitrile (Slightly), DMSO (Slightly), Methanol (Slightly)
• PKA: 3.94±0.10(Predicted)
• BRN: 2213134
• CAS DataBase Reference: 4-Hydroxy-3-nitrobenzoic acid(CAS DataBase Reference)
• NIST Chemistry Reference: 4-Hydroxy-3-nitrobenzoic acid(616-82-0)
• EPA Substance Registry System: 4-Hydroxy-3-nitrobenzoic acid(616-82-0)

Safety Data

• Hazard Codes: Xn,Xi
• Statements: 36/37/38
• Safety Statements: 26-37/39-24/25-36
• WGK Germany: 3
• TSCA: T
• HazardClass: IRRITANT
• Hazardous Substances Data: 616-82-0(Hazardous Substances Data)

Usage

Chemical Properties

yellow to light brown powder

Uses

Standard in chymotrypsin assays

General Description

4-Hydroxy-3-nitrobenzoic acid was coupled to ionic liquid-immobilized o-phenylenediamine to form benzimidazole derivatives.

InChI:InChI=1/C7H5NO5/c9-6-2-1-4(7(10)11)3-5(6)8(12)13/h1-3,9H,(H,10,11)/p-2

Synthetic route

4-hydroxy-benzoic acid (99-96-7) → 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With magnesium(II) nitrate hexahydrate; AMA at 20℃; for 1.5h; Neat (no solvent); regioselective reaction;	98%
With dimethylbromosulphonium bromide; tetrabutylammonium nitrite In acetonitrile at 20℃; for 2h; regioselective reaction;	93%
With trichloroisocyanuric acid; silica gel; sodium nitrite In dichloromethane at 20℃; for 0.333333h;	87%

4-chloro-3-nitrobenzoate (96-99-1) → 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With water; sodium hydroxide at 100℃;	98%
With sodium hydroxide In water at 95℃; for 10h;	91.83%
With sodium hydroxide In water	430 g (90 %)

3-nitro-4-fluorobenzoic acid (453-71-4) → 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With acetylhydroxamic acid; potassium carbonate In dimethyl sulfoxide at 80℃; for 1h; Sealed tube;	93%

4-hydroxy-benzoic acid (99-96-7) → 4-nitro-phenol (100-02-7) + 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With ammonium cerium(IV) nitrate In acetonitrile at 20℃; for 0.333333h;	A 10% B 84%

4-hydroxy-benzoic acid (99-96-7) → 2,4-Dinitrophenol (51-28-5) + 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With ammonium cerium(IV) nitrate In acetonitrile at 60 - 70℃; for 0.25h;	A 45% B 50%
With ammonium cerium(IV) nitrate In acetonitrile at 60 - 70℃; for 0.25h;	A 50% B 50%
With chloroform; nitric acid

p-hydroxybenzamide (619-57-8) → 3-nitro-4-hydroxybenzoic acid (616-82-0) + 2-nitro-4-hydroxybenzoic acid (74230-08-3) + 4-hydroxy-benzoic acid (99-96-7)

Conditions	Yield
With acetic acid; isopentyl nitrite at 80℃; for 21h; Inert atmosphere;	A 39% B 43% C 13%

3,4-Dihydroxybenzoic acid (99-50-3) → 2,4-Dinitrophenol (51-28-5) + 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With diethyl ether; cis-nitrous acid

1-methyl-4-nitrosobenzene (623-11-0) + 3,4-dinitrobenzoic acid (528-45-0) → 3-nitro-4-hydroxybenzoic acid (616-82-0)

1-methyl-4-nitrosobenzene (623-11-0) + (4-methoxycarbonyl-2-nitro-phenoxy)-acetic acid → 3-nitro-4-hydroxybenzoic acid (616-82-0)

1-methyl-4-nitrosobenzene (623-11-0) + 4-methoxycarbonylmethoxy-3-nitro-benzoic acid (476313-40-3) → 3-nitro-4-hydroxybenzoic acid (616-82-0)

1-methyl-4-nitrosobenzene (623-11-0) + 2-(4'-methoxy-3'-nitro-α'-oxo-bibenzyl-α-ylmercapto)-benzoic acid (855469-12-4) → 3-nitro-4-hydroxybenzoic acid (616-82-0) + 2-(benzylthio)benzoic acid (1531-80-2)

4-hydroxymethyl-2-nitrophenol (41833-13-0) → 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With alkaline permanganate at 90 - 100℃;

2,5-dihydroxy-3,6-bis(4-hydroxyphenyl)cyclohexa-2,5-diene-1,4-dione (519-67-5) → 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With nitric acid

4-carboxymethoxy-3-nitro-benzoic acid (25253-99-0) + furan-2,3,5(4H)-trione pyridine (1:1) → 3-nitro-4-hydroxybenzoic acid (616-82-0)

4-carboxymethoxy-3-nitro-benzoic acid (25253-99-0) → 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With sodium hydroxide

methyl 4-(2-methoxy-2-oxo-ethoxy)-3-nitrobenzoate (83785-14-2) + furan-2,3,5(4H)-trione pyridine (1:1) → 3-nitro-4-hydroxybenzoic acid (616-82-0) + 4-carboxymethoxy-3-nitro-benzoic acid (25253-99-0)

4-amino-benzoic acid (150-13-0) → 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With chloroform; sulfur dioxide; nitric acid

p-carboxybenzene diazonium nitrate + toluene (108-88-3) → 3-nitro-4-hydroxybenzoic acid (616-82-0)

4-amino-3-nitrobenzoic acid (1588-83-6) → 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With potassium hydroxide

4-carboxy-2-nitrophenyl heptanoate (43049-38-3) → oenanthic acid (111-14-8) + 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With phosphate buffer; alpha cyclodextrin at 25℃; Rate constant; also in the presence of β-cyclodextrin, var. conc. of α- and β-cyclodextrin;

4-(acetyloxy)-3-nitrobenzoic acid (1210-97-5) → 3-nitro-4-hydroxybenzoic acid (616-82-0) + acetic acid (64-19-7)

Conditions	Yield
1,3-dimethyl-1H-imidazol-3-ium bromide In ethanol at 23.9℃; Rate constant; var. catalyst - imidazolium salts, var. pH, var. composition of solvent, var. conc. of catalyst;
With phosphate buffer; alpha cyclodextrin at 25℃; Rate constant; also in the presence of β-cyclodextrin;

4-carboxy-2-nitrophenyl butanoate (56003-42-0) → 3-nitro-4-hydroxybenzoic acid (616-82-0) + butyric acid (107-92-6)

Conditions	Yield
With phosphate buffer; alpha cyclodextrin at 25℃; Rate constant; also in the presence of β-cyclodextrin, var. conc. of α-cyclodextrin;

3-nitro-4-hexanoyloxybenzoic acid (65293-27-8) → 3-nitro-4-hydroxybenzoic acid (616-82-0) + hexanoic acid (142-62-1)

Conditions	Yield
With phosphate buffer; alpha cyclodextrin at 25℃; Rate constant; also in the presence of β-cyclodextrin, var. conc. of α- and β-cyclodextrin;

3-nitro-4-propionyloxybenzoic acid (86868-06-6) → 3-nitro-4-hydroxybenzoic acid (616-82-0) + propionic acid (802294-64-0)

Conditions	Yield
With phosphate buffer; alpha cyclodextrin at 25℃; Rate constant; also in the presence of β-cyclodextrin, var. conc. of α-cyclodextrin;

4-carboxy-2-nitrophenyl pentanoate (67880-44-8) → 3-nitro-4-hydroxybenzoic acid (616-82-0) + valeric acid (109-52-4)

Conditions	Yield
With phosphate buffer; alpha cyclodextrin at 25℃; Rate constant; also in the presence of β-cyclodextrin, var. conc. of α-cyclodextrin;

4-carboxy-2-nitrophenyl 4-methylpentanoate (137363-37-2) → 4-Methylpentanoic acid (646-07-1) + 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With phosphate buffer; alpha cyclodextrin at 25℃; Rate constant; also in the presence of β-cyclodextrin;

4-carboxy-2-nitrophenyl 2-ethylhexanoate (137363-36-1) → 2-Ethylhexanoic acid (149-57-5) + 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With phosphate buffer; alpha cyclodextrin at 25℃; Rate constant; also in the presence of β-cyclodextrin;

3-nitro-4-(octanoyloxy)benzoic acid (113894-26-1) → Octanoic acid (124-07-2) + 3-nitro-4-hydroxybenzoic acid (616-82-0)

Conditions	Yield
With phosphate buffer; alpha cyclodextrin at 25℃; Rate constant; also in the presence of β-cyclodextrin, var. conc. of α- and β-cyclodextrin;
With Tris-HCl buffer; water; calcium(II) ion; sodium chloride; Agkistrodon piscivorus piscivorus In acetonitrile at 37℃; Rate constant; pH = 8.0;

4-carboxy-2-nitrophenyl 4-t-butylbenzoate (143671-56-1) → 3-nitro-4-hydroxybenzoic acid (616-82-0) + 4-(1,1-dimethylethyl)benzoic acid (98-73-7)

Conditions	Yield
With phosphate buffer; β‐cyclodextrin; sodium chloride In acetonitrile at 25℃; Rate constant; pH 7.65; also with ether CD or PEI alone;

C25H20N2O10 (143671-58-3) → 3-nitro-4-hydroxybenzoic acid (616-82-0) + 4-(1,1-dimethylethyl)benzoic acid (98-73-7)

Conditions	Yield
With phosphate buffer; β‐cyclodextrin; sodium chloride In acetonitrile at 25℃; Rate constant; pH 7.65; also with ether CD or PEI alone;

3-nitro-4-hydroxybenzoic acid (616-82-0) → 4-hydroxymethyl-2-nitrophenol (41833-13-0)

Conditions	Yield
With borane-THF; boron trifluoride diethyl etherate In tetrahydrofuran for 18h;	100%
With borane-THF; boron trifluoride diethyl etherate In tetrahydrofuran at 20℃; for 18h;	93%
With borane-THF In tetrahydrofuran at 0 - 20℃; for 20h; Inert atmosphere;	91%

methanol (67-56-1) + 3-nitro-4-hydroxybenzoic acid (616-82-0) → methyl (4-hydroxy-3-nitro)benzoate (99-42-3)

Conditions	Yield
With sulfuric acid for 12h; Inert atmosphere; Schlenk technique; Reflux;	98%
With sulfuric acid for 16h; Heating;	93%
With Amberlite IR-120(H+) for 168h;	93%

3-nitro-4-hydroxybenzoic acid (616-82-0) → 3-amino-4-hydroxybenzoic acid (1571-72-8)

Conditions	Yield
With hydrogenchloride; tin(ll) chloride at 0℃; for 1h; Reflux;	98%
With hydrogenchloride; tin(ll) chloride In tetrahydrofuran; water at 0℃; for 1h;	98%
With hydrogenchloride; tin(ll) chloride In water at 0℃; for 1h; Reflux;	98%

3-nitro-4-hydroxybenzoic acid (616-82-0) → 4-Hydroxy-3-nitrobenzoyl chloride

Conditions	Yield
	97.6%
With pyridine; thionyl chloride for 1.5h; Reflux;
With thionyl chloride In 1,2-dimethoxyethane at 80℃;

ethanol (64-17-5) + 3-nitro-4-hydroxybenzoic acid (616-82-0) → ethyl 4-hydroxy-3-nitrobenzoate (19013-10-6)

Conditions	Yield
With sulfuric acid for 72h; Fischer esterification; Reflux;	97%
With sulfuric acid for 12h; Reflux;	96%
With hydrogenchloride at 20℃;	95%

methanol (67-56-1) + 3-nitro-4-hydroxybenzoic acid (616-82-0) → methyl 3-amino-4-hydroxybenzoate (536-25-4)

Conditions	Yield
With thionyl chloride at 20℃; for 16h;	95%

pentan-1-ol (71-41-0) + 3-nitro-4-hydroxybenzoic acid (616-82-0) → pentyl 4-hydroxy-3-nitrobenzoate

Conditions	Yield
With sulfuric acid for 72h; Fischer esterification; Reflux;	95%

3-nitro-4-hydroxybenzoic acid (616-82-0) + ethyl iodide (75-03-6) → ethyl 4-ethoxy-3-nitrobenzoate (937625-32-6)

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide at 50℃; for 72h; Inert atmosphere;	94%
With potassium carbonate In DMF (N,N-dimethyl-formamide) at 90℃;

3-nitro-4-hydroxybenzoic acid (616-82-0) + phenol (108-95-2) → phenyl 4-hydroxy-3-nitrobenzoate (1089331-13-4)

Conditions	Yield
With dmap; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride In dichloromethane at 20℃; for 1.5h;	92%

3-nitro-4-hydroxybenzoic acid (616-82-0) + benzyl bromide (100-39-0) → 4-(benzyloxy)-3-nitrobenzoic acid (17903-89-8)

Conditions	Yield
Stage #1: 3-nitro-4-hydroxybenzoic acid; benzyl bromide With potassium carbonate In acetone Heating; Stage #2: With sodium hydroxide In methanol at 20℃; for 3h; Further stages.;	91.5%

3-nitro-4-hydroxybenzoic acid (616-82-0) + isopropyl alcohol (67-63-0) → isopropyl 4-hydroxy-3-nitrobenzoate (52791-72-7)

Conditions	Yield
With sulfuric acid at 170℃; for 8h;	91%
With sulfuric acid for 48h; Inert atmosphere; Reflux;	2.11 g

3-nitro-4-hydroxybenzoic acid (616-82-0) → 2-hydroxynitrobenzene (88-75-5)

Conditions	Yield
With sulfolane; sodium hydrogencarbonate at 200℃; for 2h;	91%

3-nitro-4-hydroxybenzoic acid (616-82-0) → tert-butyl 4-hydroxy-3-nitrobenzoate (273939-22-3)

Conditions	Yield
With sodium bicarbonate; sulfuric acid; magnesium sulfate In dichloromethane; tert-butyl alcohol	90%

3-nitro-4-hydroxybenzoic acid (616-82-0) → C7H7NO3*H3O4P

Conditions	Yield
With phosphoric acid; palladium on activated carbon; hydrogen at 95℃; under 7500.75 - 10501.1 Torr; for 5h; Autoclave;	88.5%

3-nitro-4-hydroxybenzoic acid (616-82-0) + methyl chloroformate (79-22-1) → 4-methoxycarbonyloxy-3-nitrobenzoic acid

Conditions	Yield
With sodium hydroxide In water	86%
With sodium hydroxide In water

chloro-trimethyl-silane (75-77-4) + 3-nitro-4-hydroxybenzoic acid (616-82-0) → 3-nitro-4-trimethylsiloxybenzoic acid trimethylsilyl ester (79302-41-3)

Conditions	Yield
With triethylamine In toluene for 2h; Heating;	84%

3-nitro-4-hydroxybenzoic acid (616-82-0) + trimethoxonium tetrafluoroborate (420-37-1) → methyl (4-hydroxy-3-nitro)benzoate (99-42-3)

Conditions	Yield
With diisopropylamine In dichloromethane	82%

n-Dodecylamine (124-22-1) + 3-nitro-4-hydroxybenzoic acid (616-82-0) → N-dodecyl-4-hydroxy-3-nitrobenzamide (70382-09-1)

Conditions	Yield
Stage #1: n-Dodecylamine; 3-nitro-4-hydroxybenzoic acid With benzotriazol-1-ol In N,N-dimethyl-formamide at 0℃; for 0.0833333h; Inert atmosphere; Stage #2: With 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; N-ethyl-N,N-diisopropylamine In N,N-dimethyl-formamide at 0 - 20℃; for 5h; Inert atmosphere;	80%
Stage #1: n-Dodecylamine; 3-nitro-4-hydroxybenzoic acid With benzotriazol-1-ol In N,N-dimethyl-formamide at 0℃; for 0.0833333h; Inert atmosphere; Stage #2: With 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; N-ethyl-N,N-diisopropylamine In N,N-dimethyl-formamide at 20℃; for 5h; Inert atmosphere;	80%

3-nitro-4-hydroxybenzoic acid (616-82-0) + bis-[(trifluoroacetoxy)iodo]benzene (2712-78-9) → phenyliodine(III) bis(4-hydroxy-3-nitrobenzoate) (89563-20-2)

Conditions	Yield
In acetonitrile	74%

3-nitro-4-hydroxybenzoic acid (616-82-0) + acetic anhydride (108-24-7) → 4-(acetyloxy)-3-nitrobenzoic acid (1210-97-5)

Conditions	Yield
With sodium hydroxide for 0.0333333h;	70%
With sodium hydroxide
With triethylamine In N,N-dimethyl-formamide
With pyridine at 25℃; for 3h;
With pyridine at 20℃; for 65h;

3-nitro-4-hydroxybenzoic acid (616-82-0) + acryloyl chloride (814-68-6) → 4-carboxy-2-nitrophenylacrylate

Conditions	Yield
With triethylamine In acetonitrile Ambient temperature;	70%

3-nitro-4-hydroxybenzoic acid (616-82-0) + isobutylamine (78-81-9) → 4-hydroxy-N-isobutyl-3-nitro-benzamide (909255-49-8)

Conditions	Yield
With benzotriazol-1-ol; N-(3-dimethylaminopropyl)-N-ethylcarbodiimide In dichloromethane at 5 - 20℃; for 9h;	70%

3-nitro-4-hydroxybenzoic acid (616-82-0) + sodium hydrogencarbonate (144-55-8) → methyl (4-hydroxy-3-nitro)benzoate (99-42-3)

Conditions	Yield
With sulfuric acid In methanol; 1,2-dichloro-ethane	68%

3-nitro-4-hydroxybenzoic acid (616-82-0) + 4-methylbenzenesulfonic acid n-hexylester (3839-35-8) → hexyl 4-hydroxy-3-nitrobenzoate (885620-29-1)

Conditions	Yield
Stage #1: 3-nitro-4-hydroxybenzoic acid With sodium hydrogencarbonate In N,N-dimethyl acetamide Heating; Stage #2: 4-methylbenzenesulfonic acid n-hexylester In N,N-dimethyl acetamide for 1h; Heating;	67%

3-nitro-4-hydroxybenzoic acid (616-82-0) + benzyl bromide (100-39-0) → C21H17NO5 (79520-01-7)

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide at 20℃;	64%

n-hexanoic anhydride (2051-49-2) + 3-nitro-4-hydroxybenzoic acid (616-82-0) → 3-nitro-4-hexanoyloxybenzoic acid (65293-27-8)

Conditions	Yield
With sulfuric acid In ethyl acetate at 65℃; for 0.25h;	62%
With sulfuric acid at 85 - 90℃; for 4h;

Upstream product

• 99-50-3 3,4-Dihydroxybenzoic acid 
• 41833-13-0 4-hydroxymethyl-2-nitrophenol 
• 108-88-3 toluene 
• 1210-97-5 4-(acetyloxy)-3-nitrobenzoic acid 
• 520-18-3 kaempferol 
• 7697-37-2 nitric acid 
• 7732-18-5 water 
• 99-96-7 4-hydroxy-benzoic acid 
• 60-29-7 diethyl ether 
• 7664-93-9 sulfuric acid 
• 861789-63-1 [4-(4-chloro-3-nitro-benzoylamino)-3-nitro-phenyl]-arsonic acid 
• 453-71-4 3-nitro-4-fluorobenzoic acid 
• 74-11-3 para-chlorobenzoic acid 
• 619-57-8 p-hydroxybenzamide 

Downstream Products

• 99-42-3 methyl (4-hydroxy-3-nitro)benzoate 
• 34384-48-0 4-hydroxy-3-nitro-benzoic acid propyl ester 
• 59719-77-6 4-ethoxy-3-nitrobenzoic acid 
• 19013-10-6 ethyl 4-hydroxy-3-nitrobenzoate 
• 10463-17-9 3-iodo-4-hydroxy-5-nitrobenzoic acid 
• 1210-97-5 4-(acetyloxy)-3-nitrobenzoic acid 
• 67175-27-3 3-bromo-4-hydroxy-5-nitro-benzoic acid 
• 1571-72-8 3-amino-4-hydroxybenzoic acid 
• 861306-34-5 4-ethoxycarbonyloxy-3-nitro-benzoic acid 
• 35288-44-9 3-nitro-4-propoxybenzoic acid 
• 89563-20-2 phenyliodine(III) bis(4-hydroxy-3-nitrobenzoate) 
• 937625-32-6 ethyl 4-ethoxy-3-nitrobenzoate 
• 536-25-4 methyl 3-amino-4-hydroxybenzoate 
• 273939-22-3 tert-butyl 4-hydroxy-3-nitrobenzoate 

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