Question
What is nucleophilic substitution reaction ? Write down different products obtained from alkyl halides.
✓
Answer
$\rightarrow$ Nucleophiles are electron rich species.
Therefore, they attack at that part of the substrate molecule which is electron deficient.
$\rightarrow $ The reaction in which a nucleophile replaces already existing nucleophile in a molecule is called nucleophilic substitution reaction.
$\rightarrow$ Haloalkanes are substrate in these reactions.
$\rightarrow$ In this type of reaction, a nucleophile reacts with haloalkane $($the substrate$)$ having a partial positive charge on the carbon atom bonded to halogen.
$\rightarrow$ A substitution reaction takes place and halogen atom, called leaving group departs as halide ion.
Since the substitution reaction is initiated by a nucleophile, it is called nucleophilic substitution reaction.
$\rightarrow$ It is one of the most useful classes of organic reactions of alkyl halides in which halogen is bonded to $SP^3$ hybridised carbon.
$\ce{R - X + Nu ^{-} \rightarrow R - Nu + X ^{-}}$
Therefore, they attack at that part of the substrate molecule which is electron deficient.
$\rightarrow $ The reaction in which a nucleophile replaces already existing nucleophile in a molecule is called nucleophilic substitution reaction.
$\rightarrow$ Haloalkanes are substrate in these reactions.
$\rightarrow$ In this type of reaction, a nucleophile reacts with haloalkane $($the substrate$)$ having a partial positive charge on the carbon atom bonded to halogen.
$\rightarrow$ A substitution reaction takes place and halogen atom, called leaving group departs as halide ion.
Since the substitution reaction is initiated by a nucleophile, it is called nucleophilic substitution reaction.
$\rightarrow$ It is one of the most useful classes of organic reactions of alkyl halides in which halogen is bonded to $SP^3$ hybridised carbon.
$\ce{R - X + Nu ^{-} \rightarrow R - Nu + X ^{-}}$
| Reagent | Nucleophile $(Nu^-)$ |
Substitution product $R-Nu$ |
Class of main product |
| $NaOH (KOH)$ | $HO^-$ | $ROH$ | Alcohol |
| $H₂O$ | $H₂O$ | $ROH$ | Alcohol |
| $NaOR'$ | $R'O^-$ | $ROR'$ | Ether |
| $Nal$ | $Γ$ | $R-I$ | Alkyl iodide |
| $NH_3$ | $NH_3$ | $RNH_2$ | Primary amine |
| $R'NH₂$ | $R'NH_2$ | $RNHR'$ | Sec. amine |
| $R'R"NH$ | $R'R"NH$ | $RNR'R"$ | Tert. amine |
| $KCN$ | $\overline{ C } \equiv N :$ | $RCN$ | Nitrile $($cyanide$)$ |
| $AgCN$ | $Ag-CN$ | $RNC$ | Isonitrile $($isocyanide$)$ |
| $KNO_2$ | $O = N - O$ | $R-O-N=O$ | Alkyl nitrite |
| $AgNO_2$ | $Ag -\ddot{ O }- N = O$ | $R-NO_2$ | Nitroalkane |
| $R'COOAg$ | $R'COO^-$ | $R'COOR$ | Ester |
| $LiAlH _4$ | $H$ | $RH$ | Hydrocarbon |
| $R'^-M^+$ | $R'$ | $RR'$ | Alkane |
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