What Is Biphenyl Definition Structure Formula Reactions and Uses
Biphenyl forms colorless crystals and is an organic compound. The compounds contain the functional group consisting of biphenyl less one hydrogen. It has a comparatively pleasant smell. It is an aromatic hydrocarbon with the molecular formula(C6H15)2. It is a starting material for the production of PCBs. PCBs (PCB polychlorinated biphenyls) were once widely used as dielectric fluids and heat transfer agents.
It is an intermediate for the production of a host of another compound. The compounds are emulsifiers, optical brighteners, crop protection products, and plastics. Biphenyl cannot be dissolved in water but is soluble in organic solvents. Biphenyl occurs naturally in coal tar and crude oil. It can be isolated from these sources via distillation. It is produced industrially as a byproduct of dealkylation to produce benzene. Biphenyl can be synthesized by treatment of phenylmagnesium bromide with copper(II) salts. This process is carried on in the laboratory.
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Structure of a Biphenyl
Reactions and Uses of Biphenyl
Biphenyl is non-reactive due to its lack of functional groups. The functional groups are the basis of its application. In labs, biphenyl is mainly used as a heat transfer agent as a eutectic mixture with diphenyl ether. This mixture is kept stable at 400 degrees.
Biphenyl undergoes sulfonation which followed by base hydrolysis, produces p-hydroxyphenyl. This is a useful fungicide. These reactions undergo halogenation. Polychlorinated biphenyls are also known as PCB polychlorinated biphenyls were once popular pesticides.
Lithium biphenyl contains the radical anion. Many solvates of alkali metal salts of biphenyl anion have been characterized by X-Ray crystallography. Lithium biphenyl offers an advantage relative to the related lithium naphthene.
Methyl Biphenyl
It is a colorless nonflammable and highly toxic gas. It is readily liquified. It comprises the family of organic halogen compounds. Used as a fumigant against insects and rodents. Its smaller amount is used in the preparation of other organic compounds. Methyl bromide is manufactured when methanol is reacted with hydrobromic acid. Methyl Biphenyl has a molecular formula of C12H12. The other synonyms used for Methyl Biphenyl are 4-Methylbiphenyl, 4-Phenyltoluene, 644-08-6, 4-Methyl-1, 1-methyl-4-phenyl benzene. It comprises a molecular weight of 168.23g/mol.
Dimethyl Biphenyl
It states its molecular formula of C14H14. The other synonyms found of 2 methyl Biphenyl are 4,4’-Dimethylbiphenyl, 613-33-2, 4,4’-Dimethylniphenyl, 4,4’-Bitolyl, 4,4’Dimethyl-1,1’biphenyl. It has a molecular weight of 182.26g/mol.
Biphenyl Sigma Aldrich
Sigma Aldrich is a life science and biotechnology company, before 2014 it was known as Sigma Aldrich. It was created by the 1975 merger of Sigma chemicals company and Aldrich chemical company. The company has its headquarters in St. Louis and has operations in nearly 40 countries.
The company is a supplier in the research and fine chemicals market. It provides organic as well as inorganic chemicals, building blocks, reagents, advanced materials, and stable isotopes for chemical synthesis, medical chemistry, and materials science. Biphenyl sigma is Sigma Aldrich’s main biochemical supplier, with offerings that are included. The offerings here included buffers, carbohydrates, antibodies, enzymes, forensic tools, histology and haematology, proteins, amino acids, and their derivatives, peptides, nucleotides.
Isopropyl Biphenyl
It has a molecular formula of C15H16. Its relative synonyms are 2-isopropyl biphenyl, ISOPROPYL BIPHENYL, (1-phenyl-2-propane-2-yl)benzene, 19486-60-3, UNII-W161X7N5AA. It has a molecular weight of 196.29g/mol. It has IUPAC name of 1-phenyl-2-propan-2-ylbenzene.
Distyryl Biphenyl
It has a molecular formula of C28H22. Its many of synonyms include distyrylbiphenyl, ZINC2077606, 1-[(E)-2-phenylethenyl]-2-[2-[(E)-2-phenylethenyl]phenyl]benzene, AKOS004901829, 2,2’-bis(2-phenylvinyl)-1,1’-biphenyl.
It has a molecular weight of 358.5g/mol.
FAQs on Biphenyl in Organic Chemistry Structure Properties and Applications
1. What is biphenyl in chemistry?
Biphenyl is an aromatic hydrocarbon consisting of two benzene rings directly bonded together, with the molecular formula C12H10.
- It is also called diphenyl.
- Its structure is written as C6H5–C6H5.
- Both rings are aromatic and connected by a single C–C bond.
- It is a nonpolar, crystalline solid at room temperature.
2. What is the molecular formula and molar mass of biphenyl?
The molecular formula of biphenyl is C12H10, and its molar mass is approximately 154.21 g·mol-1.
- Carbon: 12 × 12.01 = 144.12 g·mol-1
- Hydrogen: 10 × 1.008 = 10.08 g·mol-1
- Total ≈ 154.21 g·mol-1
3. What is the structure of biphenyl?
The structure of biphenyl consists of two benzene rings joined by a single carbon–carbon (C–C) bond.
- Each ring is planar and aromatic.
- The single bond between the rings allows rotation.
- Due to steric hindrance between ortho hydrogens, the rings are usually slightly twisted rather than perfectly coplanar.
4. Is biphenyl aromatic?
Yes, biphenyl is aromatic because each benzene ring satisfies Hückel’s rule (4n + 2 π electrons).
- Each benzene ring contains 6 π electrons (n = 1).
- The aromaticity is localized in each ring.
- The single bond connecting the rings does not disrupt aromatic stability.
5. How is biphenyl prepared in the laboratory?
Biphenyl is commonly prepared by the Fittig reaction, which couples two aryl halides using sodium metal in dry ether.
- General reaction: 2C6H5Cl + 2Na → C6H5–C6H5 + 2NaCl
- Occurs in dry ether as solvent.
- Forms biphenyl as a coupling product.
6. What type of reactions does biphenyl undergo?
Biphenyl mainly undergoes electrophilic aromatic substitution reactions similar to benzene.
- Nitration: introduction of –NO2 group using HNO3/H2SO4.
- Halogenation: reaction with Cl2 or Br2 in presence of FeCl3/FeBr3.
- Sulfonation: reaction with fuming H2SO4.
7. What are the physical properties of biphenyl?
Biphenyl is a colorless to white crystalline solid with moderate volatility and a characteristic odor.
- Molecular formula: C12H10
- Molar mass: 154.21 g·mol-1
- Insoluble in water but soluble in organic solvents like ethanol and ether.
- Nonpolar due to its hydrocarbon structure.
8. What is the difference between biphenyl and benzene?
The main difference between biphenyl and benzene is that benzene has one aromatic ring (C6H6), while biphenyl has two benzene rings joined together (C12H10).
- Benzene: single planar ring with 6 π electrons.
- Biphenyl: two aromatic rings connected by a single C–C bond.
- Biphenyl has higher molar mass and boiling point than benzene.
9. What are the uses of biphenyl?
Biphenyl is used as a heat transfer medium, preservative, and intermediate in chemical synthesis.
- Used in heat transfer fluids due to thermal stability.
- Applied as a fungistat to preserve citrus fruits.
- Used in the manufacture of polychlorinated biphenyls (PCBs) and dyes.
10. What are polychlorinated biphenyls (PCBs)?
Polychlorinated biphenyls (PCBs) are chlorinated derivatives of biphenyl in which one or more hydrogen atoms are replaced by chlorine atoms.
- General formula: C12H10−nCln (where n = 1–10).
- They were widely used as coolants and insulating fluids.
- PCBs are chemically stable but environmentally persistent and toxic.
