106-38-7

Basic information

• Product Name: Benzene,1-bromo-4-methyl-
• Synonyms: Toluene,p-bromo- (8CI);1-Bromo-4-methylbenzene;1-Methyl-4-bromobenzene;4-Bromo-1-methylbenzene;4-Methyl-1-bromobenzene;4-Methylbromobenzene;4-Methylphenyl bromide;4-Tolyl bromide;NSC 6531;p-Bromo(methyl)benzene;p-Bromotoluene;p-Methylbromobenzene;p-Methylphenyl bromide;p-Tolyl bromide;4-Bromotoluene
• CAS NO: 106-38-7
• Molecular Formula: C₇H₇Br
• Molecular Weight: 171.0345
• EINECS: 203-391-8
• Product Categories: alkyl bromide;Building Blocks;Chemical Synthesis;Halogenated Hydrocarbons;Organic Building Blocks;Intermediates;Aromatic Hydrocarbons (substituted) & Derivatives;Organics;Miscellaneous;4-Alkylbromobenzenes (Building Blocks for Liquid Crystals);Building Blocks for Liquid Crystals;Functional Materials;Aryl;C7;Halogenated Hydrocarbons
• Mol File: 106-38-7.mol

Chemical Properties

• Melting Point: 26-29℃
• Boiling Point: 183.8 °C at 760 mmHg
• Flash Point: 69 °C
• Appearance: colourless or pale yellow liquid
• Density: 1.39 g/cm³
• Vapor Pressure: 1.04mmHg at 25°C
• Refractive Index: 1.548
• Storage Temp.: Store below +30°C.
• Solubility: 0.11g/l insoluble
• Water Solubility: <0.1 g/100 mL at 24℃
• Merck: 14,1439
• BRN: 1903636
• CAS DataBase Reference: Benzene,1-bromo-4-methyl-(CAS DataBase Reference)
• NIST Chemistry Reference: Benzene,1-bromo-4-methyl-(106-38-7)
• EPA Substance Registry System: Benzene,1-bromo-4-methyl-(106-38-7)

Safety Data

• Hazard Codes: Xn:Harmful
• Statements: R22:; R36/37/38:
• Safety Statements: S26:; S37/39:
• RIDADR: UN 3077 9/PG 3
• WGK Germany: 3
• RTECS: XS7965600
• TSCA: Yes
• HazardClass: 9
• PackingGroup: III
• Hazardous Substances Data: 106-38-7(Hazardous Substances Data)

Usage

Uses

Used in Organic Synthesis:
Benzene,1-bromo-4-methylis used as a starting material for organic synthesis, particularly in the synthesis of ketones through Cu/Pd-catalyzed decarboxylative cross-coupling reactions. It is also utilized in the Heck reaction with styrene in the presence of in situ generated palladium complexes of phosphine-functionalized N-heterocyclic carbene ligands.
Used in Pharmaceutical Manufacturing:
In the pharmaceutical industry, Benzene,1-bromo-4-methylis used as a raw material for the manufacturing of various organic compounds, including antihypertensive drugs such as losartan and Irbesartan.
Used in Chemical Intermediates:
Benzene,1-bromo-4-methylserves as a raw material for the production of chemical intermediates like p-bromobenzyl, p-bromodibromobenzyl, and p-bromobenzaldehyde.
Used in Solvent Applications:
Due to its solubility properties, Benzene,1-bromo-4-methylcan be used as a solvent in various industrial applications, including paints, paint thinners, and glues.

References

https://www.sigmaaldrich.com/catalog/search?term=4-Bromotoluene&interface=All&N=0&mode=match%20partialmax&lang=en®ion=US&focus=product https://bbzfrankie.wordpress.com/2013/11/21/application-of-4-bromotoluene/ https://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?dbs+hsdb:@term+@DOCNO+6015

Preparation

4-Bromotoluene is prepared by diazotization and replacement of p-toluidine. First, add aqueous sulfuric acid solution to crushed p-toluidine while hot, cool to 5°C, and slowly add aqueous sodium nitrite solution until the starch potassium iodide test paper turns blue. Then add a small amount of urea to destroy the excess of sodium nitrite. Then add the synthesized cuprous bromide to hydrobromic acid, heat it to boiling, then slowly add the above diazo salt and distill it until no oil-like substance comes out. Wash, dry, filter, distill at atmospheric pressure and collect 183-185℃ fraction to obtain 4-Bromotoluene.

Synthesis Reference(s)

Organic Syntheses, Coll. Vol. 1, p. 136, 1941Tetrahedron, 64, p. 4999, 2008 DOI: 10.1016/j.tet.2008.03.085

Air & Water Reactions

Insoluble in water.

Reactivity Profile

4-Bromotoluene is incompatible with strong oxidizing agents.

Fire Hazard

4-Bromotoluene is combustible.

Safety Profile

Moderately toxic by inhalation and intraperitoneal routes. When heated to decomposition it emits toxic vapors of Br-.

Purification Methods

Crystallise it from EtOH [Taylor & Stewart J Am Chem Soc 108 6977 1986]. [Beilstein 5 IV 827.]

InChI:InChI:1S/C7H7Br/c1-6-2-4-7(8)5-3-6/h2-5H,1H3

Upstream product

• 108-32-7 1,2-propylene cyclic carbonate 
• 128-08-5 N-Bromosuccinimide 
• 118-75-2 chloranil 
• 108-88-3 toluene 
• 94-36-0 dibenzoyl peroxide 
• 57573-52-1 4-methylbenzene diazonium 
• 20614-06-6 bis(4-bromobenzyl) ether 
• 31543-75-6 2,4-dibromotoluene 
• 106-49-0 p-toluidine 
• 104-15-4 toluene-4-sulfonic acid 
• 537-64-4 bis(p-tolyl)mercury 
• 685-87-0 Diethyl 2-bromomalonate 
• 359-45-5 N-bromo-trifluoroacetamide 
• 18620-02-5 (4-bromophenyl)magnesium bromide 

Downstream Products

• 31053-03-9 N-(4-methylphenyl)piperidine 
• 71982-24-6 N-(3-methylphenyl)piperidine 
• 69239-35-6 Chlorbis(4-methylphenyl)phenylmethan 
• 622-96-8 4-methylethylbenzene 
• 101273-46-5 1-(4′-methylphenyl)isoquinoline 
• 1595-05-7 p-butyltoluene 
• 56403-26-0 1-bromo-2,5-bis(chloromethyl)-4-methylbenzene 
• 1231244-85-1 2-(5-bromo-2-methylphenyl)acetonitrile 
• 203314-29-8 2-bromo-5-methylphenylacetic acid 
• 854646-94-9 2-(5-bromo-2-methylphenyl)acetic acid 
• 124778-32-1 1,6-di(p-tolyl)hexane 
• 644-08-6 4-Methylbiphenyl 
• 5440-76-6 (4-methylphenyl)diphenylmethanol 
• 18412-57-2 p-tolyltriethoxysilane 

Relevant articles and documents

Novel site-specific one-step bromination of substituted benzenes

Regiospecific bromination of benzene derivatives has been carried out with Me2SO-HBr; this method gives excellent yields of 2-bromobenzaldehyde and 2-bromonitrobenzene; strong ortho- and para-directing monosubstituted benzenes give para-bromo derivatives; a general discussion of the mechanism of these reactions is given.

A simple and improved procedure for selective ring bromination of alkyl-substituted aromatic hydrocarbons on the surface of alumina

Highly selective ring bromination of alkyl-substituted aromatic hydrocarbons has been achieved using molecular bromine adsorbed on the surface of alumina without any solvent.

Induced bromination of aromatic hydrocarbons by alkali metals bromides and sodium hypochlorite

Induced bromination of aromatic compounds in a system MBr-acid-NaOCl was studied. Optimum conditions of the process were developed, kinetics of the reactions were investigated, and the process mechanism was suggested. The bromination occurs both with the bromine in statu nascendi and with the hypobromous acid by hydrogen substitution exclusively in the aromatic ring. 2005 Pleiades Publishing, Inc.

Bromination of alkylbenzenes in 1-butyl-3-methylimidazolium bromide and its dibromide complex

Alkylbenzenes were subjected to bromination with molecular bromine using 1-butyl-3-methylimidazolium bromide as solvent. A complex of 1-butyl-3-methylimidazolium bromide with bromine was synthesized. It ensured bromination of alkylbenzenes with no bromine and solvent. The results of bromination in binary solvents and ionic liquids, 1-butyl-3-methylimidazolium bromide and tribromide were compared. The bromination of ethylbenzene with 1-butyl-3-methylimidazolium tribromide was accompanied by formation of a considerable amount of α-bromoethylbenzene, which is not typical of electrophilic aromatic substitution process.

Deoxygenation of carbonyl compounds using an alcohol as an efficient reducing agent catalyzed by oxo-rhenium complexes

This work describes the first methodology for the deoxygenation of carbonyl compounds using an alcohol as a green solvent/reducing agent catalyzed by oxo-rhenium complexes. The system 3-pentanol/ReOCl3(SMe2)(OPPh3) was successfully employed in the deoxygenation of several aryl ketones to the corresponding alkenes and also in the deoxygenation of aryl aldehydes to alkanes with moderate to excellent yields. The catalyst ReOCl3(SMe2)(OPPh3) can also be used in several catalytic cycles with good activity.

Regioselective bromination of aromatic compounds with Br 2/SO2Cl2 over microporous catalysts

A new selective brominating system Br2/SO2Cl 2/zeolite, has been discovered. Partially cation-exchanged Ca 2+-Y zeolite efficiently catalyzes the selective para-bromination of neat chlorobenzene (CB) by Br2/SO2Cl2 affording a CB conversion of ～89% and a para-selectivity of ～97%. During the bromination reaction, SO2Cl2 oxidizes HBr, prevents its accumulation within the zeolite pores and yields a more active brominating species. The Ca2+-Y catalyst was found to be stable under the bromination conditions, and can easily be regenerated by calcination. The Br2/SO2Cl2/Ca2+-Y brominating system could be applicable to other activated aromatic compounds such as o-xylene, toluene and fluorobenzene.

A new method of bromination of aromatic rings by an iso-amyl nitrite/HBr system

A mixture of iso-amyl nitrite/HBr is shown to be a mild and efficient reagent for electrophilic aromatic bromination. The reaction succeeds with slightly activated arenes and heterocyclic compounds. By using HCl instead of HBr, chlorination can also be performed in few cases. The i-amONO2/HBr mixture can also be utilized for bromination in the α-position of electron withdrawing groups. A possible mechanism is briefly discussed.

Reactivities of Several Nucleophiles toward 4-Methylbenzyne in Very Hot Water

By means of competition experiments, the relative rates of reaction of several nucleophiles with 4-methylbenzyne in aqueous solution at temperatures up to 318 deg C have been determined.The relative nucleophilicities vs. chloride ion are as follows: PhS-, 46; I-, 6.2; piperidine, 3.0; Br-, 1.7; aniline, 1.3; Cl-, (1.0); PhO-, 1.0; ammonia, 0.55; F-, 0.20.For all but PhS-, piperidine, and iodide, the p/m product ratio is 0.83+/-0.02.In the cases of PhS- and piperidine a competing mechanism of ipso substitution, probably involving catalysis by copper ions, caused the observed p/m ratios to be high and variable.Our experimental design precluded determination of the p/m ratio for iodide ion.Because of chemical complications, only rough estimates could be made of the nucleophilicities of nitrite and benzenesulfinate ions.

Halogenation of Aromatic Compounds by using Sodium Perborate as an Oxidant

A facile method for the halogenation of benzene and its derivatives by aqueous haloacids (HCl and HBr) using sodium perborate as an oxidising agent in the presence of tertabutylammonium bromide as a phase transfer catalyst is described.

Bipyridinium and Phenanthrolinium Dications for Metal-Free Hydrodefluorination: Distinctive Carbon-Based Reactivity

The development of novel Lewis acids derived from bipyridinium and phenanthrolinium dications is reported. Calculations of Hydride Ion Affinity (HIA) values indicate high carbon-based Lewis acidity at the ortho and para positions. This arises in part from extensive LUMO delocalization across the aromatic backbones. Species [C10H6R2N2CH2CH2]2+ (R=H [1 a]2+, Me [1 f]2+, tBu [1 g]2+), and [C12H4R4N2CH2CH2]2+ (R=H [2 a]2+, Me [2 b]2+) were prepared and evaluated for use in the initiation of hydrodefluorination (HDF) catalysis. Compound [2 a]2+ proved highly effective towards generating catalytically active silylium cations via Lewis acid-mediated hydride abstraction from silane. This enabled the HDF of a range of aryl- and alkyl- substituted sp3(C?F) bonds under mild conditions. The protocol was also adapted to effect the deuterodefluorination of cis-2,4,6-(CF3)3C6H9. The dications are shown to act as hydride acceptors with the isolation of neutral species C16H14N2 (3 a) and C16H10Me4N2 (3 b) and monocationic species [C14H13N2]+ ([4 a]+) and [C18H21N2]+ ([4 b]+). Experimental and computational data provide further support that the dications are initiators in the generation of silylium cations.