Alcohols, Phenols and Ethers 2025 NEET Class Notes PDF
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2025
NEET
Pankaj Sir (POPU MAMA)
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Summary
These class notes cover the topic of Alcohols, Phenols and Ethers, focusing on the preparation of alcohols by Grignard reagents and the mechanisms involved. It also includes various practice questions and reactions.
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# YAKEEN 2.0 FOR NEET 2025 ## Lecture-03 Organic Chemistry ### Alcohols, Phenols and Ethers By- Pankaj Sir(POPU MAMA) Physics Wallah ## Topics to be Covered 1. Methods of Preparation of Alcohols Part 03 2. Grignard Reagent 3. Practice ## Methods of Preparation of Alcohols ### 3. By Grignard...
# YAKEEN 2.0 FOR NEET 2025 ## Lecture-03 Organic Chemistry ### Alcohols, Phenols and Ethers By- Pankaj Sir(POPU MAMA) Physics Wallah ## Topics to be Covered 1. Methods of Preparation of Alcohols Part 03 2. Grignard Reagent 3. Practice ## Methods of Preparation of Alcohols ### 3. By Grignard Reagent - Acid base rxns are fastest $R-x$ + $Mg$ dry ether $Rmgx$ $pactas$ $Base$ $Rmgx$ + $ROH$ → $R-H$ $8^-$ $Rmgx$ + $RCOOH$ → $R-H$ $2$ $mg$ $x$ $As$ $a$ $Nu$ $Carbonyl$ $Gepoxy$ $(NAR)$ $Nucleophilic$ $addition$ $γλη$ $(SNAE)$ $Nucleophilic$ $addition$ $followed$ $by$ $elimination$ $Acid$ $Derivative$ ## Mechanism of NAR in carbonyl compound **General Mechanism** $Nu$ $sp^2 \rightleftharpoons C=O$ $8^-$ $Nu$ $A$ $Nu$ $C-OH$ $sp^3$ $Nu$ $H+$ $from$ $H_2O$ $ROH$ $RCOOH$ $NH3$ $(NH_4Cl)$ $C-OH$ $Nu$ ## ROR of NAR 1. **Steric Factor** $ROR \propto 1$ $SH$ - steric hinderance (Bulkness) $H-C =O > R-C=O > R-C=O$ $H$ $H$ $R$ 2. **Electronic Factor** $R-O.R \propto Electrophilicity$ $of$ $carbonyl$ $Carbon$ $H-C=O > R-C=O > R-C=O$ $H$ $H$ $R$. ## NAR in GR $C=O$ + $Rmgx$ → $C-O^+Mgx$ + $H_2O$ → $C-OH + mg(OH)x$ $R$ $R$ $R$ ## Reaction of GR with Cyclic Ether - $only$ $3$ $&$$4$ $membered$ $cyclic$ $ether$ $can$ $react$ $with$ $GR$ $lesshindered$ $more$ $hindered$ $O$ $2$ $H+ \downarrow$ $O$ $1^o$ $Rmgx$ → $R$ $O$ $mgx$ $R$ → $OH$ $R$ $2^o$ $Rmgx$ → $O \downarrow$ $1^o$ $R$ $omp$ $R$ → $H+$ $OH$ $R$ ## Mechanism of SNAE in Acid Derivatives (General SNAE) $R-C-Z $ $St$ $Nu$ $Addition \Rightarrow R-C-Z$ $Nu$ $OCOR$ $OR$ $NR_2$ $Elimination \Rightarrow R-C-Nu + Z$ $O$ $Nu$ **Acid Derivatives:** - $RCl$ (Acid Chloride) - $R-CO-OOR$ (Acid Anhydride) - $R-CO-OR$ (Ester) - $R-CO-NR_2$ (Amide) **In 1 & 2 Amide** $R-C-N-R$ + $Acid$ +$Base$ → $HO$ $Jati$ $O$ $H$ $R-C-N-hai$ $O$ $H$ ## ROR of SNAE 1. **Electronic Factor** $ROR \propto Electrophilicity$ $a$ $ewg$ $ a$ $ -I$ $ +I$ $edg$ $ +M$ power $ +M$ power $ +M$ power $ +M$ power $R-C-Cl > R-C-OCOR > R-C-FOR > R-C-N-R_2$ 2. **Steric Factor** $NR_2 > OR > O-C-R $ $O$ $H$ $CH_3$ $R$ $R$ $R$ ## SNAE in GR $R-C-Z$ + $Rmgx$ → $R-C-Z$ → $R-C-R + Zmgx$ $O$ $R$ $R$ $R$ $Acid$ $derivative$ $Rmgx$ → $Ketone$ $Rmgx$ → $Alcohol $ $R”mgx$ $2. H+ (NAR)$ $OH$ $R-C-R’$ $ |$ $R”$ $3^o Alcohol$ ## QUESTION **Assertion**: Two moles of Grignard reagent is consumed in the formation of tertiary alcohol from ester followed by hydrolysis. **Reason**: One mole of Grignard reagent converts ester into ketone and the second mole of Grignard reagent adds to ketone. **Options:** * A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion. * B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion. * C. Assertion is correct but Reason is incorrect. * D. Both Assertion and Reason are incorrect. **Answer**: A **QUESTION** Write the product of these chemical reactions. **Options:** * A. \(PhMgBr + \) **ether** \(H^o\) \( Ph \) * B. \(CH_3MgBr + Ph-C-C_2H_5\) **ether** \(H^{o}\) \(Ph-C-CH_3\) $O$ $O$ $CH_3$ $OH$ * C. \(C_2H_3MgBr + Ph-C-CH_3\) **ether** \(H^o\) \(Ph-C-CH_3\) $O$ $O$ $CH_3$ $OH$ * D. \(CH_3CH_2CH_2 MgBr + PhCHO\) **ether** \(H^{o}\) \(Ph-CH-OH\) $CH_3CH_2CH_3$ **Answer**: D ## QUESTION Which of the following compound can produce chiral compound upon treatment with CH3MgCl and then acidification? **Options:** * A. **Formaldehyde** \(H-C=O\) * B. **Pentanone-2 ** \(CH_3-C=O\) $npr$ * C. **2-hexanone** \( CH_3 - C=O\) $npr$ * D. **3-hexanone** \(Et-C=O\) $npr$ **Answer**: B ## QUESTION The reaction of Grignard reagent with formaldehyde followed by acidification gives: **Options:** * A. an aldehyde * B. a ketone * C. A carboxylic acid * D. A primary alcohol **Answer**: D ## QUESTION 3-methyl-3-hexanol cannot be prepared by **Options:** * A. \(CH_3MgI\) and 3-Hexanone, followed by hydrolysis * B. \(C_2H_5MgI\) and 2-Pentanone, followed by hydrolysis * C. \(C_3H_7MgI\) and 2-Butanone followed by hydrolysis * D. \(C_4H_9MgI\) and proparone, followed by hydrolysis **Answer:** C ## QUESTION When \(CH3MgI\`\)is made to react with acetone and the addition product is hydrolysed, we get : **Options:** * A. primary alcohol * B. secondary alcohol * C. tertiary alcohol * D. an aldehyde **Answer**: C ## QUESTION Phenyl magnesium bromide reacts with methanol to give: **Options:** * A. a mixture of anisole and Mg(OH) Br * B. a mixture of benzene and Mg(OMe) Br * C. a mixture of toluene and Mg(OH) Br * D. a mixture of phenol and Mg(Me) Br **Answer**: B ## QUESTION Ethyl acetate reacts with \( CH_3MgBr\) to form: **Options:** * A. secondary alcohol * B. tertiary alcohol * C. primary alcohol and an acid * D. an acid **Answer**: B ## QUESTION Reaction of esters with Grignard reagents give rise to: **Options:** * A. primary alcohols * B. secondary alcohols * C. tertiary alcohols * D. ketones **Answer**: D ## QUESTION Which of the following compound does not react with methyl magnesium bromide to produce tertiary alcohol? **Options:** * A. 3-methyl pentanal * B. Ethyl benzoate * C. 4, 4-dimethylcyclohexanone * D. 4-heptanone **Answer**: B ## QUESTION \(Et-O-C=O-Et\) \(CH_3MgBr\) \(H_3O^+\), Product (A) is: **Options:** * A \(CH3-C-O-Et\) * B \(CH3-C-CH3\) $O$ * C \(CH3-C-CH3\) $OH$ $ |$ $CH_3$ * D \(CH3-CH2-CH3\) **Answer**: C ## QUESTION \(Et-O-C=O-Et\) \(CH_3MgBr\) \(H_3O^+\), Product (A) is: **Options:** * A \(CH3=C-O-Et\) * B \(CH3-C-CH3\) $O$ * C \(CH3-C-CH3\) $OH$ $ |$ $CH_3$ * D \(CH3-CH2-CH3\) **Answer**: C ## QUESTION \(Et-O-C=O-Et\) \(CH_3MgBr\) (excess) \(H_3O^+\), Product (A) is: **Options:** * A \(CH3-C-O-Et\) * B \(CH3-C-CH3\) $O$ * C \(CH3-C-CH3\) $OH$ $ |$ $CH_3$ * D \(CH3-CH2-CH3\) **Answer**: C ## QUESTION \(CH - C = O\) \(CH_3MgBr (excess)\) \(H^{o}\) $CH_3$ $C-CH_3$ $ |$ $CH_3$ $3^o Alcohol$ - Acid-Base Rxn ko NAR & SNAE ke baad nahi karate \(H_O-CH_2-CH_2-C=O- H \) \(CH_3MgBr (1 eq)\) \(H^o\) \( CH_3-MgBr (CH_3\) $O$ $2$ $CH_2OH$ ## QUESTION \(ABR > R-C-Cl > R-C-OCOR > HCHO > RCHO > RCOR > RCOOR > RCONR_2\) \(Acid \) \(Base \) \(rxn\) - \(C-O \) $CH_3$ $C$ $C=O$ $H$ $O$ $C$ $O$ - \(1^{st} mol G.R\) \(O \) \(2^{nd}mol G.R\) \(CO \) \(3^{rd}mol G.R\) \(CHO\) \(4^{th}mol G.R\) \(CO \) $CO \) \(5^{th} mol G.R\) \(COOR\) - \(1^{st} mol G.R\) \(O \) \(2^{nd}mol G.R\) \(CO \) \(3^{rd}mol G.R\) \(CHO\) \(4^{th}mol G.R\) \(CO \) \(CO \) \(5^{th} mol G.R\) \(COOR\) ## QUESTION \(C - O \) $CH_3$ $C$ $C=O$ \(H\) $O$ $C$ $O$ \(1. Excess MemgBr \) \(2. H^+ \ \) \( CH_3\) $CH_3$ \(C-CH_3 \) $ |$ $CH_3$ $OH$ \(H^+ \downarrow\) \(O \) \(CH_3\) \(C- \) \(OH\) $CH_3$ \(C=O\) $CH_3$ \(O\) \(C=O\) \(O \) \(mgBr \) \(CH_3\) \(C- \) \(H \) \(O\) $CH_3$ \(C- \) \(H\) $O$ $CH_3$ $C- $ $H$ ## QUESTION Total no of moles of G.R consumed? \(CH_3- N - C \) \(SH\) $O$ $CH_3$ \(CH_3- N - C\) $O$ $CH_3$ $H$ $O$ \(Ans =7 mol\) ## QUESTION \(H-C=O\) \(R-C=O\) \(H\) \(H\) \(Alco\) \(Ald\) In which of the following reaction \(2^O\) alcohol is obtained as a product? **Options:** * A. \(YY \) \(CH_3MgBr\) \(H_2O\) * B. \(CH_3 \) \(O \) \(MgCl \) \(H_2O\) * C. \(YY\) \(CH_3MgBr\) \(H_2O\) * D. Both (A) and (B) **Answer**: D ## QUESTION All of the following compound react with ethyl magnesium bromide. Alcohols are formed from three of the compounds. Which does not give as alcohol? **Options:** * A. \(Ph \) \(C=O\) $O$ * B. \(Ph \) \(COCH_3\) $O$ * C. \(Ph \) \(CH_2OCCCH_3\) $O$ * D. \(Ph-O-C-O-H \) $O$ **Answer**: D ## Home Work **Prabal**: Q 30, 32 **Parikshit: ** Q 06 ## Thank you!!
