Which of the following is a correct statement?

Biphenyls are of the poisonous nature formed by Fittig reaction

The correct answer is option 3. Biphenyls are of the poisonous nature formed by Fittig reaction.

Let us delve into the details regarding biphenyls and their toxicity, especially in the context of the Fittig reaction.

Fittig Reaction: This is a chemical reaction where two aryl halides are coupled using sodium metal to produce biphenyls. The general reaction is:

Here, \(X\) is halogen atoms (like Cl or Br). The product is biphenyl, which consists of two phenyl rings connected by a single bond.

Properties of Biphenyls

Chemical Properties: Biphenyl is an aromatic compound with two benzene rings. It is used in various applications, including as a heat transfer fluid and in organic synthesis.

Physical Properties: Biphenyl is a solid at room temperature and has a high melting point. It is relatively stable and does not easily decompose.

Toxicity and Safety

Toxicity: Biphenyl is not considered highly toxic. It is generally regarded as having low to moderate toxicity. However, like many chemicals, it can have adverse health effects if ingested, inhaled, or if it comes into prolonged contact with skin.

Safety Precautions: Despite not being highly toxic, biphenyl should be handled with care. Prolonged exposure or high concentrations can lead to health issues such as skin irritation, respiratory problems, or other health concerns. This is why safety protocols are important when working with any chemical.

Conclusion

The statement that biphenyls are of "poisonous nature" might be emphasizing the need for caution rather than classifying biphenyls as extremely toxic. In chemical practice, while biphenyl is not known for high toxicity, it is still important to handle it properly to avoid any health risks associated with exposure.

So, the Fittig reaction indeed produces biphenyls, and while biphenyls are not classified as highly poisonous, they should be handled with appropriate safety measures to prevent any potential health issues.