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Good Earth School Naduveerapattu Class: XII Chemistry Organic Name Reactions (1) Aldol condensation: Two molecules of an aldehyde or ketone containing πΌ-H atom undergo condensation in presence of a base to yield an aldol which loses water molecule to form unsaturated aldehyde or ketone. O OH πΌ π·ππ.ππππ» H O CH3 β C β H + H β CH2CHO οΏ½β―β―β―β―β―β―οΏ½ CH3 β C β C β C β H H HAldol - H2Oβ O CH3 β C = C β C β H H H But-2en-l-al (2) Benzoin condensation: In presence of KCN, aromatic aldehydes containing no πΌH atom, undergo self condensation to form benzoin. O OH π΄ππ.πΎπΆπ 2 C β H οΏ½β―β―β―β―β―οΏ½ O CβC H (Benzoin) (3) Bouveault-Blanc reduction: Esters on reduction with sodium in alcohols yield primary alcohols. ππ/πΆ2 π»5 ππ» CH3COOC2H5 + 4[H] οΏ½β―β―β―β―β―β―β―β―β―οΏ½ 2C2H5OH (4) Balz-Schiemann reaction: Decomposition of heating at 150°C - 160°C yields any fluoride. + N2Clβ N2π΅πΉ4β + HBF4 Benzene diazonium chloride diazoniumfluoroborate F 150°πΆβ160°πΆ οΏ½β―β―β―β―β―β―β―β―οΏ½ Benzene diazonium Fluoroborate + BF3 + N2 Fluoro benzene upon (5) Cannizzaroβs reaction: Aldehydes which do not have an πΌ -hydrogen atom undergo this reaction. When such aldehydes are treated with concentrated solution of an alkali, they form alcohol and salt of carboxylic acid. ππππ.ππππ» HCHO + HCHO οΏ½β―β―β―β―β―β―οΏ½ CH3OH + HCOONa Methanol Sodium formate ππππ.ππππ» C6H5CHO + C6H5CHO οΏ½β―β―β―β―β―β―οΏ½ C6H5CH2OH + C6H5COONa Benzyl alcohol Sodium benzoate (6) Carbyl amine reaction: When primary amine is warmed with chloroform and an alcoholic solution of KOH, it forms isocyanide having an extremely unpleasant smell. β C2H5NH2 + CHCl3 + 3KOH οΏ½β―β―β―οΏ½ C2H5N= οΏ½οΏ½βC + 3KCl + 3H2O Ethyl amine (alc.) NH2 β Aniline + CHCl3 + 3KOH οΏ½β―β―β―οΏ½ (alc) Ethyl isocyanide N= οΏ½οΏ½βC + 3KCl + 3 H2O Phenyl isocyanide (7) Claisen condensation: It involves self condensation of two molecules of ester containing πΌ -hydrogen in the presence of a strong base such as sodium ethoxide to form π½-keto ester. O O πΆ2 π»5 πππ O O CH3βCβOC2H5 + HβCH2βCβOC2H5οΏ½β―β―β―β―β―οΏ½CH3βCβCH2βCβOC2H5 + C2H5OH 2 molecules of ester Ethyl acetoacetate (8) Clemmensen reduction: It involves the reduction of aldehydes and ketones to the corresponding hydrocarbons with amalgamated zinc and conc.HCl. ππ/π»π CH3CHO + 4H Conc. οΏ½β―β―β―οΏ½ CH3CH3 + H2O HCl Acetaldehyde ππ/π»π Ethane CH3COCH3 + 4H οΏ½β―β―β―οΏ½ CH3CH2CH3 + H2O Acetone Conc. HCl Propane (9) Coupling reaction: The reaction of diazonium salts with phenols and aromatic amines to form azo compounds in presence of ice cold solution.β 273β278πΎ.ππ» β Cl + H N2 OH οΏ½β―β―β―β―β―β―β―β―β―β―οΏ½ βπ»πΆπ N=N p-Hydroxyazobenzene (orange dye) 273β278πΎ.ππ» β N2 Cl + H NH2οΏ½β―β―β―β―β―β―β―β―β―β―οΏ½ βπ»πΆπ OH N=N OH p-Aminoazobenzene (yellow dye) (10) Diazonotisation reaction: The formation of diazonium salt from primary amine in dilute mineral acid and treatment with cold solution of nitrous acid (NaNO2 + dil. HCl) at 273 β 278 K Nβ‘ ππΆπ β NH2 + ππππ2 /π»πΆπ + HONO οΏ½β―β―β―β―β―β―β―οΏ½ 273K β 278K + 2H2O Benzenediazonium chloride (11) Etardβs reaction: The oxidation of toluene to benzaldehyde with chromyl chloride dissolved in CCl4 or CS2. OCr(OH)Cl2 CH3 CH CHO OCr(OH)Cl2 π»3 π + 2πΆππ2 πΆπ2 οΏ½β―β―β―β―β―οΏ½ πͺπͺππ Toluene οΏ½β―β―οΏ½ Brown complex Benzaldehyde (12) Finkelstein reaction: Iodoalkanes can be easily prepared from the corresponding chloro or bromoalkanes by heating with sodium iodide in acetone or methanol. π΄πππ‘πππ ππ πππ‘βππππ CH3CH2Br +NaI οΏ½β―β―β―β―β―β―β―β―β―β―β―β―β―β―β―β―β―β―οΏ½ β Bromoethane CH3CH2I + NaBr Iodoethane (13) Fitting reaction: This reaction involves the reaction between two molecules of an aryl halide with sodium metal in presence of dry ether to form a diaryl. For example: Cl + 2Na + Cl π·ππ¦ ππ‘βππ οΏ½β―β―β―β―β―β―β―β―β―οΏ½ ` + 2NaCl Diphenyl or biphenyl (14) Friedel Crafts lakylation: Benzene and other aromatic compounds react with alkyl halides in the presence of anhydrous AlCl3 to form alkyl benzene. CH3 π΄πβπ¦π.π΄ππΆπ3 + CH3Cl οΏ½β―β―β―β―β―β―β―β―οΏ½ + HCl Methyl Chloride Toluene The alkylation of benzene can also be carried out with propene in presence of phosphoric acid. + CH3CH = CH2 π»3 ππ4 οΏ½β―β―β―οΏ½ 543K CH(CH3)2 Cumene (15) Friedel Crafts acylation: Benzene and other aromatic compounds react with acid chlorides or anhydrides in presence of anhydrous AlCl3 to form ketones. COCH3 Benzene π΄πβπ¦.π΄ππΆπ3 + CH3COCl οΏ½β―β―β―β―β―β―β―οΏ½ Acetyl chloride + HCl Acetophenone COCH3 Benzene π΄πβπ¦.π΄ππΆπ3 + (CH3CO)2O οΏ½β―β―β―β―β―β―β―οΏ½ Acetic anhydride + CH3COOH Acetophenone (16) Gattermann reaction: It involves the reaction of benzenediazonium chloride with Cu/HCl or Cu/HBr to prepare halorene. Cl + Nβ‘ ππΆπ β Benzenediazonium chloride πΆπ’/π»πΆπ οΏ½β―β―β―β―β―β―οΏ½ β Chlorobenzene πΆπ’/π»π΅π οΏ½β―β―β―β―β―β―οΏ½ β Bromobenzene Br + N2β + N2 (17) Gattermann Koch reaction: Benzaldehyde is prepared by passing mixture of CO and HCl gas to benzene in presence of anhydrous AlCl3 and traces of CuCl. CO + HCl β HCOCl Formyl chloride CHO + HCOCl π΄ππΆπ3 + HCl οΏ½β―β―β―β―β―οΏ½ Cucl Benzaldehyde O OH (18) Haloform reaction: The compounds containing CH3 β C β or CH3 β C β group give H yellow precipitate of iodoform on reaction with NaOH and I2 solution. This is known as iodoform reaction. CH3COCH3 + 3I2 + 4NaOH CHI3 β + CH3COONA + 3NaI + 3 H2O Acetone Iodoform (yellow ppt) CH3CH2OH + 4I2 + 6NaOH CHI3 β + HCOONa + 5NaI + 5H2O Ethanol Iodoform (19) Hell Volhard Zelinsky (HVZ) reaction: The aliphatic carboxylic acids containing πΌ-Hydrogen react with Cl2 and Br2 in presence of red phosphorus to give πΌ haloacids. ππ2 .π CH3COOH οΏ½β―β―β―β―οΏ½ CH2COOH β HCl Cl Monochloro acetic acid ππ2 .π ππ2 .π οΏ½β―β―β―β―οΏ½ Cl2CHCOOH οΏ½β―β―β―β―οΏ½ Cl3CCOOH β HCl β HCl Dichloro acetic acid Trichloroacetic acid (20) Hofmann bromamide reaction: The amides can be converted to primary amines containing one carbon less than the amides by heating it with Br2 and NaOH or KOH. It is also known as degradation reaction. β Methyl amine β Aniline CH3CONH2 + Br2 + 4KOH οΏ½β―β―β―β―οΏ½ CH3NH2 + K2CO3 + 2KBr + 2H2O Acetamide C6H5CONH2 + Br2 + 4 KOH οΏ½β―β―β―β―οΏ½ C6H5NH2 + K2CO3 + 2KBr + 2H2O Benzamide (21) Hydroboration reaction: This reaction involves addition of water to alkene according to Anti Markownikoffβs rule by addition of borane followed by hydrolysis to alcohol. π΅π»3 π»2 π2 3CH3CH = CH2 οΏ½β―β―β―β―β―β―οΏ½ (CH3CH2CH2)3 B οΏ½β―β―β―β―β―β―β―οΏ½ 3CH3CH2CH2OH THF Propene ππ» β Propanol (22) Kolbeβs electrolytic reaction: The electrolysis of sodium or potassium salt of a carboxylilc acid in aqueous solution gives alkane, alkyne as the product depending upon the nature of carboxylic acid used. For example: (i) Ethane is produced by the electrolysis of aqueous potassium acetate. 2CH3COOK 2CH3COOβ + 2K+ At anode: 2CH3CHOOβ β 2eβ 2CH3COO CH3CH3 + 2CO2 At cathode: Among K+ and H+, H+ ions are discharged due to its lesser discharge potential. 2H+ + 2eβ H2 or 2H (ii) Ethene can be obtained by the electrolysis of aqueous solution of potassium salt of succinic acid. CH2COOK CH2COOK Pot. succinate At anode: CH2COOβ CH2COOβ πΈππππ‘ππππ¦π ππ οΏ½β―β―β―β―β―β―β―οΏ½ β2π β οΏ½β―β―β―β―β―β―β―οΏ½ At cathode: 2H+ + 2eβ (iii) CH2COOβ CH2COOβ CH2COO CH2COO H2 or 2H + 2K+ β2πΆπ2 οΏ½β―β―β―β―β―β―β―β―οΏ½ CH2 CH2 Ethene Ethyne can also be obtained by the electrolysis of aqueous solution of potassium maleate. CHCOOK CHCOOK Pot. maleate At anode: CHCOOβ CHCOOβ πΈππππ‘ππππ¦π ππ οΏ½β―β―β―β―β―β―β―οΏ½ β2π β οΏ½β―β―β―β―β―β―β―οΏ½ At cathode: 2H+ + 2eβ CHCOOβ CHCOOβ CHCOO CHCOO H2 or 2H + 2K+ β2πΆπ2 οΏ½β―β―β―β―β―β―β―β―οΏ½ CH CH Ethyne (23) Kolbe-Schmidt reaction: Sodium phenoxide reacts with CO2 under 6β7 atm pressure at 400K to form sodium salicylate which upon acidification with HCl gives salicylic acid. ONa OCOONa OH COONa 400 π + CO2 οΏ½β―β―β―β―οΏ½ 6-7 atm Sodium phenoxide rearrangement Phenyl sodium carbonate Sodium salicylate H2O/H+ OH COOH (Salicylic acid) (24) Mendius reduction: The alkyl or aryl cyanide is reduced to primary amine by amalgamated sodium and alcohol. CH3CN + 4H ππ / πΆ2 π»5 ππ» οΏ½β―β―β―β―β―β―β―β―β―β―οΏ½ CH3CH2NH2 Ethyl amine (25) Rosenmundβs reaction: Acid chlorides are converted to corresponding aldehydes in presence of palladium deposited over BaSO4 partially poisoned with sulphur or quinoline. O CH3 β C β Cl + H2 Acetyl chloride O ππ, π΅πππ4 οΏ½β―β―β―β―β―β―β―β―β―οΏ½ Boiling xylene CH3 β C β H + HCl Acetaldehyde O O ππ, π΅πππ4 C6H5 β C β Cl + H2 οΏ½β―β―β―β―β―β―β―β―β―οΏ½ Benzoyl chloride S C6H5 β C β H + HCl Benzaldehyde (26) Reimer-Tiemann reaction: Phenols react with CHCl3 in presence of aqueous alkali at 340K followed by hydrolysis gives salicyldehyde. When CCl4 is taken instead of CHCl3, salicylic acid is formed. OH OH + CHCl3 + 3NaOH 340 πΎ οΏ½β―β―β―β―β―β―οΏ½ OH + 3NaCl + 2H2O Salicyladehyde OH + CCl4 + 4NaOH 340 πΎ οΏ½β―β―β―β―β―β―οΏ½ In both the cases, p-isomer is also formed. CHO COOH + 4NaCl + 2H2O Salicylic acid (27) Sandmeyerβs reaction: Benzene diazonium chlorobenzene on treatment with Cucl/HCl. π2+ πΆπ β chloride is converted to Cl πΆπ’πΆπ/π»πΆπ οΏ½β―β―β―β―β―β―β―β―β―οΏ½ Benzenediazonium chloride + N2β Chlorobenzene (28) Saponification: Hydrolysis of an ester with aqueous NaOH or KOH solution to give alcohol and the sodium or potassium salt of the fatty acid is called saponification. For example: CH2OOCR1 CHOOCR2 CH2OOCR3 CH2OH π»πππ‘ + 3 NaOH οΏ½β―β―β―β―οΏ½ CHOH R1COONa + + CH2OH Oil or fat (triglyceride) Glycerol R2COONa + R3COONa (Sodium salts of fatty acids) (29) Schotten-Baumann reaction: The treatment of benzoyl chloride with the compounds having active hydrogen like phenol, aniline, etc. in presence of aqueous NaOH is called Schotten-Baumann reaction. For example, OH OOCC6H5 ππππ» Phenol + C6H5COCl οΏ½β―β―β―β―β―β―οΏ½ Benzoyl chloride + HCl Phenyl benzoate NH2 NHCOC6H5 ππππ» Aniline + C6H5COCl οΏ½β―β―β―β―β―β―οΏ½ Benzoyl chloride + HCl Benzanilide (30) Stephen reduction: The partial reduction of alkyl or aryl cyanides to the corresponding aldehydes with a suspension of anhydrous stannous chloride in dry ether saturated with hydrogen chloride at room temperature followed by hydrolysis is called Stephen reduction or Stephen reaction. During this reaction, imine hydrochloride first gets precipitated which on hydrolysis with boiling water gives the corresponding aldehyde. For example. SnCl2 + 2HCl SnCl4 + 2[H] π·ππ¦ ππ‘βππ CH3C β‘ N + 2[H] + HCl οΏ½β―β―β―β―β―β―β―β―οΏ½ CH3CH = NH.HCl 290-295K Acetaldiminehydrochloride Boiling H2O CH3CHO + NH4Cl (31) Williamson synthesis: The reaction of alkyl halides with sodium alcoxide or sodium phenoxide to form ethers is called Williamson synthesis. ONa OCH3 + CH3I Sodium Phenoxide + NaI Methyl iodide Anisole CH3CH2I + C2H5ONa Ethyl iodide C2H5OC2H5 + NaI Sodium ethoxide Ethoxyethane (32) Wolff-Kishner reduction: The reduction is done by heating the carbonyl compound with a mixture of hydrazine and KOH in presence of ethylene glycol. ππ»2 ππ»2 πΎππ».πππ¦πππ CH3CH = O οΏ½β―β―β―β―β―β―β―οΏ½ CH3CH = NNH2 οΏ½β―β―β―β―β―β―β―β―β―β―οΏ½ CH3CH3 + N2 453 β 473k CH3 CH3 Acetone βπ―π πΆ ππ»2 ππ»2 C = O οΏ½β―β―β―β―β―οΏ½ βπ― πΆ π Hydrazone CH3 CH3 C = N.NH2 Hydrazone Ethane πΎππ».πππ¦πππ οΏ½β―β―β―β―β―β―β―οΏ½ CH3CH2CH3 + N2 453 β 473k Propane (33) Wurtz reaction: It involves the interaction of two molecules of an alkyl halide (preferably bromide or iodide) with metallic sodium in presence of dry ether to form symmetrical alkanes containing double the number of carbon atoms present in the alkyl halide. π·ππ¦ πΈπ‘βππ CH3 β Br + 2Na + Br β CH3 οΏ½β―β―β―β―β―β―β―β―β―οΏ½ CH3 β CH3 + 2NaBr Ethane However, if two different alkyl halides are used, a mixture of three alkanes are obtained. For example: π·ππ¦ πΈπ‘βππ CH3 β I + 2Na + I β CH2 β CH3 οΏ½β―β―β―β―β―β―β―β―β―οΏ½ CH3CH2CH3 + 2NaI CH3 β I + 2Na + I β CH3 οΏ½β―β―β―β―β―β―β―β―β―οΏ½ CH3 β I + 2Na + I β CH2 β CH3 οΏ½β―β―β―β―β―β―β―β―β―οΏ½ π·ππ¦ πΈπ‘βππ Propane CH3 β CH3 + 2NaI Ethane π·ππ¦ πΈπ‘βππ C4H10 + 2NaI Butane (34) Wurtz Fittig reaction: This reaction is a variation of Wurtz reaction and involves warming a mixture of an aryl halide and an alkyl halide with halide with metallic sodium in presence of dry ether to prepare homologous of benzene. For example. π·ππ¦ πΈπ‘βππ Br + 2NaI + Br β CH3 οΏ½β―β―β―β―β―β―β―β―β―οΏ½ CH3 + 2 NaBr Toluene Biphenyl and ethane are obtained as by-products.
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