Question

Which of the following is Hinsberg reagent?

• A. C$_6$H$_5$SO$_2$CH$_3$
• B. SnCl$_2$
• C. C$_6$H$_5$SO$_2$Cl
• D. CoCl$_2$

Hint:

Hinsberg reagent (C$_6$H$_5$SO$_2$Cl) is used to test amines — only primary and secondary amines react, forming sulfonamides.

Answer 1

The Correct Option is C

The Hinsberg reagent is benzene sulfonyl chloride, with the formula C$_6$H$_5$SO$_2$Cl. It is used in the Hinsberg test to distinguish between primary, secondary, and tertiary amines based on their reactivity.

• (A) C$_6$H$_5$SO$_2$CH$_3$ — methylated product, not the reagent — incorrect.
• (B) SnCl$_2$ — a reducing agent, not related to the Hinsberg test — incorrect.
• (C) C$_6$H$_5$SO$_2$Cl — correct, the Hinsberg reagent.
• (D) CoCl$_2$ — cobalt chloride, unrelated — incorrect.