Question:
Which of the following compounds will not react with Mg metal in the presence of ether to give a Grignard reagent?
Which of the following compounds will not react with Mg metal in the presence of ether to give a Grignard reagent?
Show Hint
Always check for acidic hydrogen before predicting Grignard formation.
Updated On: Apr 23, 2026
- CH$_2$=CHBr
- CH$_3$CH$_2$I
- CH$_2$OHCH$_2$Br
- CH$_3$COCH$_3$
Show Solution
Verified By Collegedunia
The Correct Option is C
Solution and Explanation
Concept:
Grignard reagents (RMgX) are formed when alkyl/aryl halides react with Mg in dry ether. However, any compound containing an acidic hydrogen (–OH, –NH, –SH) prevents their formation because it reacts with the Grignard reagent.
Step 1: Analyze each option
(A) CH$_2$=CHBr → forms Grignard reagent
(B) CH$_3$CH$_2$I → forms Grignard reagent
(C) CH$_2$OHCH$_2$Br → contains –OH group
(D) CH$_3$COCH$_3$ → no halogen, so irrelevant here
Step 2: Effect of –OH group
The –OH group has acidic hydrogen which reacts with RMgX: \[ \text{RMgX} + \text{ROH} \rightarrow \text{RH} + \text{Mg(OR)X} \] Conclusion:
Thus, CH$_2$OHCH$_2$Br does not form Grignard reagent.
Step 1: Analyze each option
(A) CH$_2$=CHBr → forms Grignard reagent
(B) CH$_3$CH$_2$I → forms Grignard reagent
(C) CH$_2$OHCH$_2$Br → contains –OH group
(D) CH$_3$COCH$_3$ → no halogen, so irrelevant here
Step 2: Effect of –OH group
The –OH group has acidic hydrogen which reacts with RMgX: \[ \text{RMgX} + \text{ROH} \rightarrow \text{RH} + \text{Mg(OR)X} \] Conclusion:
Thus, CH$_2$OHCH$_2$Br does not form Grignard reagent.
Was this answer helpful?
0
0
Top MET Chemistry Questions
- Which of the following product is formed in the reaction $ CH_3MgBr {->[(i)CO_2][(ii)H_2O]} ? $
- Ethyl chloride is converted into diethyl ether by:
- Correct order of reactivity:
- A group of 13 element if added in small amounts to Ge, then the type of semiconductor formed is
- Consider the following statements I. Repulsive forces are significant when the molecules are close together on average. II. Attractive intermolecular forces are important when the molecules are fairly close together but not necessarily touching. III. Attractive forces are ineffective when the molecules are for apart. Select correct statements.
View More Questions
Top MET Inorganic chemistry Questions
- Cane sugar on treating with conc. $\mathrm{H}_2\mathrm{SO}_4$ gives char. It is because $\mathrm{H}_2\mathrm{SO}_4$ is
- The noble gas used for treatment of cancer is
- Purification of NaCl by passage of hydrogen chloride through brine is based on
- The first compound of noble gas prepared by Bartlett was
- Which of the following is diamagnetic?
View More Questions
Top MET Questions
- A coil of 100 turns and area $2 \times 10^{-2}m^2 $ is pivoted about a vertical diameter in a uniform magnetic field and carries a current of 5A. When the coil is held with its plane in north-south direction, it experiences a couple of 0.33 Nm. When the plane is east-west, the corresponding couple is 0.4 Nm, the value of magnetic induction is [Neglect earth's magnetic field]
- $\int\limits_{0}^{8}| x -5| d x$ is equal to
- Radiation, with wavelength 6561 $?$ falls on a metal surface to produce photoelectrons. The electrons are made to enter a uniform magnetic field of $3 \times 10^{-4} T$. If the radius of the largest circular path followed by the electrons is 10 mm, the work function of the metal is close to :
- In intrinsic semiconductor at room temperature number of electrons and holes are
- Which of the following product is formed in the reaction $ CH_3MgBr {->[(i)CO_2][(ii)H_2O]} ? $
View More Questions