4433-11-8

Usage

Uses

3,4-Dimethylbiphenyl is an intermediate in the synthesis of dicarboxylic acid of biphenyls.

InChI:InChI=1/C14H14/c1-11-8-9-14(10-12(11)2)13-6-4-3-5-7-13/h3-10H,1-2H3

Upstream product

• 95-47-6 o-xylene 
• 2396-01-2 phenyl radical 
• 106-42-3 para-xylene 
• 71-43-2 benzene 
• 191541-51-2 4,4-dimethyl-1-phenylcyclohexa-2,5-dien-1-ol 
• 1124-19-2 phenyltin trichloride 
• 98-80-6 phenylboronic acid 
• 15174-47-7 α-methyl-trans-cinnamaldehyde 
• 66003-76-7 Diphenyliodonium triflate 
• 95-64-7 4-amino-o-xylene 

Downstream Products

• 4445-58-3 4-phenylphthalic acid 
• 69240-50-2 3-methylbiphenyl-4-carboxylic acid 
• 766-39-2 2,3-Dimethylmaleic anhydride 
• 124-38-9 carbon dioxide 
• 201230-82-2 carbon monoxide 
• 108-31-6 maleic anhydride 
• 955-16-8 3,4-biphenyldicarboxylic anhydride 
• 1071024-65-1 3-methyl-[1,1‘-biphenyl]-4-carbaldehyde 
• 714965-11-4 5-phenyl-1,3-dihydro-2-benzofuran-1-one 
• 2021-26-3 5-phenylisoindoline-1,3-dione 
• 4128-63-6 biphenyl-3,4-dicarbonitrile 
• 10347-14-5 2-cyano-1,4-benzenedicarbonitrile 
• 254972-84-4 3-methyl-[1,1'-biphenyl]-4-carbonitrile 
• 2920-38-9 4-cyano-1,1'-biphenyl 

Relevant academic research and scientific papers

Discovery and mechanistic investigation of Pt-catalyzed oxidative homocoupling of benzene with PhI(OAc)2

We present a Pt-catalyzed direct coupling of benzene to biphenyl. This catalytic reaction employs a cyclometalated platinum(ii) complex [PtMe(bhq)(SMe2)] (bhq = benzo[h]quinolate) with PhI(OAc)2 as an oxidant and does not require an acid, a co-catalyst or a solvent. The reaction kinetics and characterization of potential catalytic species are reported. The reaction is first-order in Pt and second-order in benzene, which implicates the second C-H activation step as rate-determining. A Pt(ii)/Pt(iv) catalytic cycle is suggested. The reaction commences by oxidation of the Pt(ii) complex to give the platinum(iv) species [Pt(bhq)(SMe2)(OAc)2](OAc) followed by C-H activation of benzene to afford the intermediate [PtPh(bhq)(SMe2)(OAc)](OAc) concurrently with the release of HOAc. A second benzene molecule reacts similarly to give the diphenyl intermediate [PtPh2(bhq)(SMe2)](OAc). C-C bond forming reductive elimination ensues to regenerate Pt(ii) and complete the catalytic cycle. The proposed mechanism has been examined by DFT computations, which provide support to experimental findings.

PtI2-catalyzed cyclization of 3-acyloxy-1,5-enynes with the elimination of HOAc and a benzyl shift: Synthesis of unsymmetrical m-terphenyls

A novel cyclization of 3-acyloxy-1,5-enynes is developed in the presence of PtI2 for the synthesis of substituted unsymmetrical m-terphenyls in good to excellent yields. Two unique steps are involved in this transformation, which includes the elimination of HOAc and benzyl group migration. DFT calculations indicated that the rate-determining step is the migration of the benzylic carbocation to form a zwitterionic intermediate followed by the elimination of HOAc. The subsequent cyclopropanation of the zwitterionic intermediate is the regioselectivity-determining step.

Palladium-catalyzed arylation of simple arenes with iodonium salts

The development of an arylation protocol for simple arenes with diaryliodonium salts using the Herrmann-Beller palladacycle catalyst is reported. The reaction takes simple aromatic feedstocks and creates valuable biaryls for use in all sectors of the chem

Iron-mediated direct arylation of unactivated arenes

(Chemical Equation Presented) Inexpensive and straightforward: An iron-mediated cross-coupling reaction generates biaryl compounds through C-H bond activation, using easily handled reagents with low toxicity. Under the optimized reaction conditions a series of substituted phenylboronic acids were coupled with several simple unactivated arenes.

Direct C-H bond arylation of arenes with aryltin reagents catalysed by palladium complexes

Direct C-H bond arylation of simple arenes with aryltin reagents has been successfully catalysed by PdCl2 in the presence of CuCl2. CuCl2 proved to be an activator for a palladium intermediate as well as an oxidant. The Royal Society of Chemistry.

Reactions and lifetime of the 6,6-dimethyl-3-phenylbenzenium ion in aqueous solution. Comparison with the 6-imino-3-phenylbenzenium ion (biphenyl-4-ylnitrenium ion)

The title cation (1) has been generated from three precursors in aqueous solution containing 20% acetonitrile; in the solvolysis of 6,6-dimethyl-3-phenylcyclohexa-2,4-dien-1-yl acetate (9) and from the isomeric alcohols 4,4-dimethyl-1-phenylcyclohexa-2,5-dien-1-ol (7) and 6,6-dimethyl-3-phenylcyclohexa-2,4-dien-1-ol (8) under acidic conditions. In addition, 8 reacts by way of 1 in weakly acidic solutions containing sodium azide to form an equilibrium mixture with an azide adduct, tentatively assigned as 6-azido-5,5-dimethyl-2-phenylcyclohexa-1,3-diene (12). This experiment provides a novel method for obtaining the kaz : kw ratio, which with the application of the azide clock method, supplies absolute rate constants. The overall analysis shows that 1 reacts in 20% acetonitrile forming 8 (90%, k = 6.2 × 106 s-1), 7 (8%, k = 5.5 × 105 s-1) plus a small amount of the rearrangement product 3,4-dimethylbiphenyl (10) (2%, k = 1.6 × 105 s-1). The pKR values are -5.3 for 1 ? 8 + H+ and -2.9 for 1 ? 7 + H+, and the equilibrium constant 7 ? 8 is 2.9 × 102. The conjugated alcohol 8 is thus both the kinetic product and the thermodynamic product of the addition of water to 1. These results are compared with ones obtained previously for the biphenyl-4-ylnitrenium ion (2), a cation which can be regarded in terms of carbenium resonance contributors as the 6-imino-3-phenylbenzenium ion. The lifetimes in aqueous solution of the two cations are similar (ca. 150 ns for 1 and 300 ns for 2), as is also the case for the rate constants for addition of water at the carbon that bears the phenyl group, the reaction that results in unconjugated alcohols. The difference is that the kinetic product with 2 is this unconjugated alcohol; an AMI calculation suggests that the conjugated isomer would be the thermodynamic product, as is the case with 1. It is suggested that the electronegative nitrogen of 2 results in a greater fraction of the positive charge being localized at the remote para carbon, so that is the site where water preferentially reacts.

Reactive Annulenones: A Comparative Study

Two new and hitherto elusive annulenones, 3-phenylcyclopentadienone and bicycloocta-1(5),3,6-triene-2,8-dione, are reported.Their lifetimes and reactivities have been studied in comparison with those of the related annulenones cyclopentadienone and 4-phenylbicycloocta-1(5),3,6-triene-2,8-dione.The influence of structure and substituents on the stabilities of these species has thereby been established.

Aromatic hydrocarbons in the gaseous and condensed phase. A nuclear decay study

A nuclear technique based on the spontaneous decay of tritiated precursors has been used in a comparative stydy of aromatic phenylation by free phenylinium ions, both in the gas and liquid phase.The mechanism of the major competitive processes promoted by phenylinium ion attack, are discussed.

Photolysis of Some ortho-Methylated Monochlorobiphenyls

A series of monochloro-o-methylated biphenyls was photolysed.Quantum yields of dechlorination lie in between the low values observed for 3- and 4-chlorobiphenyl and the high values obtained for 2-chlorobiphenyl.The results are interpreted in terms of raising the energy of the excited state due to steric crowding of the ortho-substituent and relief of strain upon the departure of an ortho-chlorine.