Alcohols from Grignard reagents and carbonyl compoundsग्रीन्यार अभिकर्मक और कार्बोनिल यौगिकों से ऐल्कोहॉलAlcohols from Grignard reagents and carbonyl compounds
Class 12 Chemistry · Chapter 7 · interactive diagram
Parts and what they mean
- Carbonyl group (C=O): Cδ+ = Oδ− (कार्बोनिल समूह (C=O): Cδ+ = Oδ−) — The electron-poor carbon is attacked by the nucleophile.
- Grignard reagent R–MgX (Rδ− is a carbanion-like nucleophile) (ग्रीन्यार अभिकर्मक R–MgX (Rδ− कार्बऋणायन जैसा नाभिकस्नेही)) — C–Mg bond is polar with carbon negative.
- Curved arrows of nucleophilic addition (नाभिकस्नेही योग के वक्र तीर) — The R–Mg bond pair attacks the C=O carbon; the π electrons of C=O move onto O.
- Adduct (magnesium alkoxide) (योगज (मैग्नीशियम ऐल्कॉक्साइड)) — The new C–R bond is formed; O carries MgX.
- Alcohol after hydrolysis (जल-अपघटन के बाद ऐल्कोहॉल) — Water replaces MgX by H, giving –OH and Mg(OH)X.
- Methanal + RMgX → primary alcohol (मेथेनैल + RMgX → प्राथमिक ऐल्कोहॉल) — HCHO has two H on the C=O carbon, so the product carbon carries R + 2H.
- Other aldehydes + RMgX → secondary alcohol (अन्य ऐल्डिहाइड + RMgX → द्वितीयक ऐल्कोहॉल) — e.g. CH₃CHO + CH₃MgBr → propan-2-ol after hydrolysis.
- Ketones + RMgX → tertiary alcohol (कीटोन + RMgX → तृतीयक ऐल्कोहॉल) — e.g. propanone + CH₃MgBr → 2-methylpropan-2-ol (NCERT Example 7.2 c).
Original diagram drawn by Simple Learning Hub, based on the NCERT textbook. Report a mistake