Alkene And Alkyne

Points to remember in Alkene & Alkyne

Characteristic Reaction

Electrophilic Addition Reaction

PYQ-2024-Hydrocarbons-Q15, PYQ-2024-Alcohol-Q5


Step 1 : Attack of the electrophile on $\pi$ bond forms a carbocation.

Step 2 : Attack by a nucleophile gives the product of addition.

e.g. (i) Addition of water

(ii) Addition of hydrogen halides (where $\mathrm{HX}=\mathrm{HCl}, \mathrm{HBr}, \mathrm{HI}$ )

When electrophiles are: $\mathrm{Cl}^{+}, \mathrm{Br}^{+}, \mathrm{I}^{+}, \mathrm{NO}_{2}^{+}$ or $\mathrm{Hg}^{2+}$ then stereochemistry is important and major product is formed by anti-addition.

Markovnikov and AntiMarkovnikov Addtion

PYQ-2024-Hydrocarbons-Q6, PYQ-2024-Hydrocarbons-Q17, PYQ-2024-Hydrocarbons-Q9, PYQ-2024-Amines-Q2,

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