Oxymercuration Demercuration Reactions

Q. 17. Reaction of Alcohol with PCl5 follows SNi or SN2 meachanism??

Q. Acid catalysed hydration of alkenes give alcohol according Markownikoff’s rule. Alcohols are also prepared from alkenes by oxy mercuration-de mercuration and hydro boration oxidation.
The Major product (x) of the following reaction is:

1. 
2. 
3. 
4. 

Q. Which of the following statements regarding the $S_{N}1$ reaction shown by alkyl halide is correct ?

1. The added nucleophile plays no kinetic role in $S_{N}1$ reaction
2. The $S_{N}1$ reaction on the chiral starting material ends up with racemisation of the product
3. The more stable the carbocation intermediate the faster the $S_{N}1$ reaction
4. All of the above

Q. The reagent X in the reactions $(C{H}_3{)}_{3}CCH=C{H}_2\underset{THF}{\stackrel{X}{}}Y\underset{NaOH}{\stackrel{NaB{H}_4}{\to }}(C{H}_3{)}_3-\underset{OH}{\underset{|}{C}}-CH-C{H}_3$

1. $H_3{O}^{+}$
2. $Hg(C{H}_{3}COO{)}_2$
3. $HCOOH$
4. $O{H}^{-}$

Q. Glyoxal on reacting with strong alkali gives

1. Glycol
2. Glycollic acid
3. Glucose
4. Glycine

Q. The reaction which does not form a tert-pentyl alcohol is:

1. 
2. 
3. 
4. 

Q. 46. What is HgOAc , the compound that is used in oxymercuretion -demercuration reaction preparation of alcohol?

Q.

What happens when Aldols readily lose water?

Q. Acid catalysed hydration of alkenes give alcohol according to Markownikoff’s rule. Alcohols are also prepared from alkenes by oxy mercuration-de mercuration and hydro boration oxidation.

(A) The compound (A) is:

1. 
2. 
3. 
4. 

Q. What is the role of pyridine in the given chemical reaction?

1. It act as nucleophile
2. It shift equilibrium toward forward reaction
3. It removes $HCl$ formed in the reaction
4. It abstract $\alpha$-hydrogen from amines

Q. The number of steps involved in $S{}_{N}1$ and $S{}_{N}2$ mechanisms are given by the set -

1. 1, 2
2. 3, 1
3. 2, 1
4. 2, 2

Q. Predict the product of below reaction:

1. 
2. 
3. 
4. 

Q. 6. During nucleophilic reactions of alcohol why is partial positive and negative charge not develpoed between carbon and oxygen It is always seen between oxygen and hydrogen like in the reaction of Alcohol and Grignard reagent

Q. Nitrobenzene on reduction with hydrogen in the presence of a catalyst gives :

1. aniline
2. azobenzene
3. azoxybenzene
4. hydrazobenzene

Q. Match the column I with column II and mark the appropriate choice.

Column I	Column II
(A) Clemmensen reduction	(i) $N{H}_{2}N{H}_2,KOH/△$
(B) Wolff-kishner	(ii) $Zn-Hg+conc.HCl$
(C) Iodoform reaction	(iii) $H_2,Pd/Pt/Ni$
(D) Catalytic hydrogenation	(iv) $NaOH+I_2$

1. (A)-(i) (B)-(iii) (C)-(ii) (D)-(iv)
2. (A)-(iii) (B)-(iv) (C)-(i) (D)-(ii)
3. (A)-(ii) (B)-(i) (C)-(iv) (D)-(iii)
4. (A)-(iv) (B)-(i) (C)-(ii) (D)-(iii)

Q. Which of the following reactions follows Markovnikovs rule?

1. $C_2{H}_4+HBr$
2. $C{H}_6+B{r}_2$
3. $C_3{H}_6+C{l}_2$
4. $C_3{H}_6+HBr$

Q. $C{H}_{3}COOH\stackrel{LiAL{H}_3}{\to }\left(A\right)$
$\left(A\right)+C{H}_{3}COOH\stackrel{H_3{O}^{+}}{\to }\left(B\right)+H_{2}O$
In the above reaction ‘A’ and ‘B’ respectively are:

1. $C{H}_{3}COO{C}_2{H}_5,C_2{H}_{5}OH$
   
   
   
2. $C{H}_{3}CHO,C_2{H}_{5}OH$
   
   
3. $9C_2{H}_{5}OH,C{H}_{3}CHO$
   
4. $C_2{H}_{5}OH,C{H}_{3}COO{C}_2{H}_5$

Q. The final product ‘C’ in the following series of reactions

Q.

The above hydration can be carried out by

\( \longrightarrow \)

Q. The difference between aldol condensation and Cannizzaro’s reaction is that:

1. the former takes place in the presence of α-H-atom
2. the former takes place in the absence of $\alpha -H-atom$
3. the former takes place in the presence of $\beta -H-atom$
4. none of the above

Q. Which of the following method(s) is/are used for synthesis of alcohols?

1. Oxymercuration-demercuration
2. Hydroboration oxidation
3. Acid-Catalysed hydration of alkenes
4. Wurtz reaction

Q. What happens when alcohols reacts with ethers

Q. The end product ‘W’, in the following sequence of reactions

1. 
2. 
3. 
4. 

Q. The Major product of reaction is:

1. 
2. 
3. 
4. None of the above

Q.

Here A is

1. 

2. 

3. 

4. 

Q. Write the name of the major organic product formed in the reaction of 1-pentene with HBr.

1. 1-bromopentane
2. 3-bromopentane
3. None of these
4. 2-bromopentane

Q. (A) and (B) is differentiated by.

1. NaH
2. $2-4$DNA
3. Tollen's reagent
4. $NaHS{O}_3$

Q. Are there any advantages of negative catalyst?

Q. A reaction proceeds in three stages. The first stage is slow and involves two molecules of reactants. The second and third stage are fast. The overall order of the reaction is:

1. second order
2. first order
3. zero order
4. third order

Q. 49. Do alcohols react with sodium?