5006-39-3

Basic information

• Product Name: 1,1'-Biphenyl, 2,3,3',4'-tetramethyl-
• CAS NO: 5006-39-3
• Molecular Formula: C16H18
• Molecular Weight: 210.319
• Mol File: 5006-39-3.mol
• Article Data: 10

Chemical Properties

• CAS DataBase Reference: 1,1'-Biphenyl, 2,3,3',4'-tetramethyl-(CAS DataBase Reference)
• NIST Chemistry Reference: 1,1'-Biphenyl, 2,3,3',4'-tetramethyl-(5006-39-3)
• EPA Substance Registry System: 1,1'-Biphenyl, 2,3,3',4'-tetramethyl-(5006-39-3)

Safety Data

• Hazardous Substances Data: 5006-39-3(Hazardous Substances Data)

Usage

General Description

1,1'-Biphenyl, 2,3,3',4'-tetramethyl- is a chemical compound with the molecular formula C18H18. It is a derivative of biphenyl, which is a common component found in a variety of industrial and consumer products. This particular compound has four methyl groups attached to different positions on the biphenyl structure, making it highly stable and resistant to chemical reactions. It is used as a building block in the synthesis of various organic compounds, and has applications in the production of polymers, dyes, and pharmaceuticals. Despite its widespread use, the compound has been subject to restrictions and regulations due to potential environmental and health concerns.

Upstream product

• 31599-61-8 3,4-dimethyliodobenzene 
• 95-47-6 o-xylene 
• 615-60-1 4-chloro-1,2-dimethylbenzene 
• 608-23-1 3-chloro-o-xylene 
• 583-71-1 4-bromo-o-xylene 
• 31599-60-7 1-iodo-2,3-dimethylbenzene 

Relevant articles and documents

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.

Palladium-Catalyzed Cross-Dehydrogenative Coupling of o-Xylene: Evidence of a New Rate-Limiting Step in the Search for Industrially Relevant Conditions

An efficient cross-dehydrogenative coupling of o-xylene under neat conditions, which brings important industrial benefits towards the synthesis of a monomer used in polyimide resins, is reported. The catalyst based on the combination of Pd/N ligand/carboxylate=1:1:2 does not require a Cu cocatalyst and proceeds at 11 bar of O2 pressure. Evaluation of the deuterium kinetic isotope effect (KIE) provides evidence for three different rate-determining steps, which depend on the reaction conditions (medium, temperature). Under the reported neat conditions, the dissociation of a carboxylate-bridged dimer to generate a more reactive monometallic Pd species is proposed to be the rate-limiting step.

A method for preparing four methyl biphenyl

The invention provides a preparation method of tetramethyl biphenyl, which comprises the following steps: mixing o-xylene, oxidizer, additive and metal catalyst, and reacting to obtain the tetramethyl biphenyl, wherein the additive is organic acid and/or organic acid anhydride, and the oxidizer is inorganic oxidizer and/or organic oxidizer containing metal cation. Compared with the prior art of synthesizing tetramethyl biphenyl from halogenated o-xylene, the invention uses the o-xylene for direct coupling to obtain the tetramethyl biphenyl. The raw material o-xylene is cheap and accessible, and the preparation of the halogenated o-xylene is not needed, so the invention lowers the production cost, is simple to operate and has the advantages of mild reaction conditions and low facility request; and under the action of the catalyst, the o-xylene is directly coupled to prepare the tetramethyl biphenyl, and all the carbon atom frameworks of the o-xylene enter the product, so the invention also has the advantage of high economical efficiency of atoms.