Reactivity of alkyl halides towards SN1 and SN2SN1 और SN2 के प्रति ऐल्किल हैलाइडों की क्रियाशीलताReactivity of alkyl halides towards SN1 and SN2

Class 12 Chemistry · Chapter 6 · interactive diagram

Parts and what they mean

• Methyl halide CH₃X (मेथिल हैलाइड CH₃X) — Fastest by SN2, slowest by SN1 (CH₃⁺ is very unstable).
• Primary halide (प्राथमिक हैलाइड) — Prefers SN2.
• Secondary halide (द्वितीयक हैलाइड) — Can go SN1 or SN2 (or elimination) depending on nucleophile/base and conditions.
• Tertiary halide (तृतीयक हैलाइड) — Fastest by SN1 (very stable 3° carbocation); practically no SN2.
• SN1 reactivity: 3° > 2° > 1° > CH₃X (SN1 क्रियाशीलता: 3° > 2° > 1° > CH₃X) — Controlled by the stability of the carbocation formed in the slow step.
• SN2 reactivity: CH₃X > 1° > 2° > 3° (SN2 क्रियाशीलता: CH₃X > 1° > 2° > 3°) — Controlled by steric hindrance to backside attack.
• R–I > R–Br > R–Cl >> R–F (R–I > R–Br > R–Cl >> R–F) — Same order for SN1 and SN2: the weaker the C–X bond, the easier X leaves.
• Allylic and benzylic halides (ऐलिलिक और बेन्ज़िलिक हैलाइड) — High SN1 reactivity: their carbocations are stabilised by resonance.

Original diagram drawn by Simple Learning Hub, based on the NCERT textbook. Report a mistake