619-04-5

Basic information

• Product Name: 3,4-Dimethylbenzoic acid
• Synonyms: RARECHEM AL BO 0330;O-XYLENE-4-CARBOXYLIC ACID;1-Carboxy-3,4-dimethylbenzene;3,4-dimethyl-benzoicaci;3,4-DIMETHYLBENZOIC ACID;AKOS BBS-00007820;ASYM-O-XYLYLIC ACID;Benzoic acid, 3,4-dimethyl- (7CI,8CI,9CI)
• CAS NO: 619-04-5
• Molecular Formula: C₉H₁₀O₂
• Molecular Weight: 150.17
• EINECS: 210-576-7
• Product Categories: CARBOXYLICACID;Aromatic Carboxylic Acids, Amides, Anilides, Anhydrides & Salts;Benzenes;Acids & Esters
• Mol File: 619-04-5.mol
• Article Data: 30

Chemical Properties

• Melting Point: 163-165 °C(lit.)
• Boiling Point: 271.51°C (estimate)
• Flash Point: 134.9 °C
• Appearance: White to beige/Crystalline Powder
• Density: 1.0937 (estimate)
• Vapor Pressure: 0.000728mmHg at 25°C
• Refractive Index: 1.5188 (estimate)
• Storage Temp.: Store below +30°C.
• PKA: 4.44±0.10(Predicted)
• Water Solubility: 129.2mg/L(temperature not stated)
• BRN: 907267
• CAS DataBase Reference: 3,4-Dimethylbenzoic acid(CAS DataBase Reference)
• NIST Chemistry Reference: 3,4-Dimethylbenzoic acid(619-04-5)
• EPA Substance Registry System: 3,4-Dimethylbenzoic acid(619-04-5)

Safety Data

• Hazard Codes: Xi,Xn
• Statements: 36/37/38-22
• Safety Statements: 22-24/25-37/39-26
• WGK Germany: 3
• RTECS: DG8734020
• TSCA: Yes
• Hazardous Substances Data: 619-04-5(Hazardous Substances Data)

Usage

Chemical Properties

white to beige crystalline powder

Definition

ChEBI: A dimethylbenzoic acid in which the two methyl groups are located at positions 3 and 4.

Purification Methods

Crystallise it from EtOH or H2O (m 168-168.5o), and sublime it in vacuo. The phenyl ester has m 68o (from EtOH or pet ether) and b 155-157o/2mm. [Beilstein 9 II 353, 9 III 2441, 9 IV 1803.]

InChI:InChI=1/C9H10O2/c1-6-3-4-8(9(10)11)5-7(6)2/h3-5H,1-2H3,(H,10,11)

Upstream product

• 56-23-5 tetrachloromethane 
• 6578-78-5 1,1-bis(3,4-dimethylphenyl)ethylene 
• 79-37-8 oxalyl dichloride 
• 95-47-6 o-xylene 
• 463-72-9 carbamic chloride 
• 95-63-6 1,2,4-Trimethylbenzene 
• 934-80-5 1,2-dimethyl-4-ethylbenzene 
• 27831-13-6 3,4-dimethylstyrene 
• 3982-66-9 1,2-dimethyl-4-propyl-benzene 
• 51036-98-7 3-(3,4-dimethylbenzoyl)propionic acid 
• 873979-12-5 2,2,2-trichloro-1-(3,4-dimethyl-phenyl)-ethanone 
• 40207-05-4 3-(chloromethyl)-4-methylbenzoic acid 
• 871896-99-0 δ-oxy-δ-(3.4-dimethyl-phenyl)-α-amylene 
• 141-53-7 sodium formate 

Downstream Products

• 3637-01-2 3,4-dimethylacetophenone 
• 95-47-6 o-xylene 
• 5156-01-4 2-methylterephthalic acid 
• 681448-23-7 3,4-dimethyl-cyclohexanecarboxylic acid 
• 95-64-7 4-amino-o-xylene 
• 16155-55-8 2-(3,4-dimethylphenyl)benzo[d]oxazole 
• 89075-57-0 2-(3,4-Dimethyl-phenyl)-3H-imidazo[4,5-c]pyridine 
• 19047-21-3 3,4-bis(dibromomethyl)benzoic acid 
• 20896-24-6 3,4-Bis(bromomethyl)benzoic acid 
• 22884-95-3 3,4-dimethylbenzonitrile 
• 6237-17-8 3-bromo-4,5-dimethylbenzoic acid 
• 4315-14-4 4,5-Dimethyl-2-nitrobenzoesaeure 
• 50419-58-4 2-amino-3,4-dimethylbenzoic acid 
• 348165-23-1 3-amino-4,5-dimethylbenzoic acid 

Relevant articles and documents

Diels-Alder reactions with 1,1-diethoxybut-3-yn-2-one and some 1,1-diethoxy-5-hydroxyalk-3-yn-2-ones and their acetates

The title compounds were reacted with a few conjugated dienes at room temperature and above. The alcohols were unreactive, but the other ynones reacted at a reasonable rate. Conceivably, the expected cyclohexa-1,4-diene adducts were formed, but they were unstable and aromatized to the corresponding benzene derivatives, which were isolated in low to excellent yield.

Highly-functionalized arene synthesis based on palladium on carbon-catalyzed aqueous dehydrogenation of cyclohexadienes and cyclohexenes

Transition metal-catalyzed dehydrogenation is a clean oxidation method requiring no additional oxidants. We have accomplished a heterogeneous Pd/C-catalyzed aqueous dehydrogenation of 1,4-cyclohexadienes and cyclohexenes to give the corresponding highly-functionalized arenes. Furthermore, various arenes could be efficiently constructed in a one-pot manner via a Diels-Alder reaction and the following dehydrogenation.

A method of preparing 1,2,4,5-benzenetetracarboxylic acid or trimellitic acid from pinacol

The invention relates to a method of preparing 1,2,4,5-benzenetetracarboxylic acid or trimellitic acid from pinacol. The method includes a first step of selectively dehydrating the pinacol in an acid/ionic liquid catalytic system to generate 2,-3-dimethyl-1,3-butadiene; a second step of subjecting the 2,-3-dimethyl-1,3-butadiene and maleate or acrylate to a D-A cycloaddition/dehydrogenation tandemreaction to generate an aromatic ring product; and a third step of subjecting the aromatic ring product to hydrolysis and oxidation to prepare the 1,2,4,5-benzenetetracarboxylic acid or the trimellitic acid. The catalytic system adopted in the method is green, and can be recycled. The raw material is a biomass-based platform chemical, and is cheap and easily available. All reaction processes aresimple. The pinacol dehydration reaction, the dehydrogenation reaction of a D-A product and an oxidation reaction are high in activity and selectivity. The novel method for preparing the 1,2,4,5-benzenetetracarboxylic acid and the trimellitic acid which are fine chemicals from the pinacol that is a lignocelluloses based platform chemical is provided by the invention.