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Derivative of carboxylic acids Acid halide )1( Nomenclature oyl halide بـalkane من اسمe باستبدال حرف- alkanoyl halide Alkane yl chloride بـic أو من اسم الحمض باستبدال- Preparations Chemical reactions Reaction of acid chloride with R-MgX Hell volhard zelinski H2 O H3C C C Cl propionyl chloride Cl2 P )2( Acid anhydride H H3C C Cl O C Cl anhydride التسمية تتم بذكر اسم الحمض متبوعاً بكلمــة- Preparation ( 1 ) From acid chloride )2( From acetylene )3( From ketene Chemical reactions )3( Amide التسمية تتم بذكر اسم alkaneمحذوفاً منه حرف eواستبداله بـ amideأو اسمالحمض محذوفاً منه oicواستبدالها بـ amide Preparation of amides )1( From acid chloride, anhydride, ester )2( From nitriles ) 3 ( From ammonium salt Chemical reactions ) 1 ( Hydrolysis ) 2 ( Hofmann degradation of amide Q. Convert acetic acid to methyl amine اإلجابـة ) 3 ( Dehydration ( 4 ) Action of nitrous acid )4( Esters التسمية تتم كاآلتي-: -1ذكر اسم `R -2ذكر اسم الحمض محذوفاً منه -icومضافاً اليه ate Ortho ester Fats esters .e.g Preparation 4) CH3COOAg + C2H5Br CH3COOC2H5 + AgBr 5) RCOOH + CH2N2 RCOOCH3 + N2 6) H2C C O + C2H5OH CH3COOC2H5 7) CHCl3 + C2H5ONa CH(OC2H5)3 Reactions of esters Reaction with Grignard to form t-alc Mechanism Claisen condensation of ester Mechanism Substituted products of monocyclic acids 1. Halogenated acids . على حسب موقع الهالوجينδ ، γ ، β ، α تقسم الى Preparation of α-halo acid 1. Hell-Volhard-Zelinski reaction Iodo derivative can be prepared as follow 2. From α-hydroxy acid preparation of β-halogenated acid alkene الحظ اإلضافة تتم عكس قاعدة ماركنكوف في حاله اتصال سلسله-COOH أو بمجموعه الدهيد أو كيتون 2. From hydroxy acid Preparation of γ-Halogenated acid CH2=CH-CH2COOH + HBr BrCH2CH2CH2COOH Reactions of Halogenated acid Effect of NaOH on Halogenated acids 1. Effect of NaOH on α-Halo acid ClCH2COOH +NaOH HOCH2COONa 2. Effect of NaOH on β -Halo acid ClCH2CH2COOH +NaOH CH2=CHCOOH Acrylic acid 3. Effect of NaOH on γ – and δ-Halo acid (B) Hydroxy acids OH على حسب موقعδ ، γ ، β ، α تقسم الى- أسماء يجب حفظها- Preparation of Hydroxyacids 1) Preparation ofα-hydroxy acid 1. From halogenated acid 2. From aldehyde or ketones O CH3CH +HCN OH CH3CH-CN H3O + OH CH3CH-COOH Lactic acid 2) Preparation of β-hydroxy acid Reformatsky reaction 3) Preparation of γ & δ-hydroxy acids Chemical reactions 1) Action of heat 1- α-hydroxy acid 2- β-hydroxy acid 3- γ-hydroxy acid or δ-hydroxy acid 2) Action of PCl3 3) Reduction with HI (C) Amino acids Preparation of amino acids (2) Streacker’s synthesis (3) Gaberial synthesis Gaberial synthesis can be used for synthesis amino acids & amines a) For synthesis of amino acids e.g. Glycine Question: Convert Phthalimide to Glycine ? Reaction of amino acids 1) Amphoteric character of amino acid Amino acids are amphoteric because it contains both acidic –COOH thus it is present in an inner salt (B) which is , group and basic group –NH2 Zeitter ion called In acidic medium it exist in (C) In basic medium it exist in (A) Isoelectric point of amino acid It is the pH at which the amino acid exists as the inner salt (B) 2) Reactions of amino group a) Conversion to hydroxy acid b) Acetylation 3) Effect of heat 1- α-amino acid 2- β-Amino acid 3- γ- Amino acid or δ- Amino acid Dicarboxlic acids Examples General methods of preparation of dicarboxylic acids:1.oxidation of glycols: 2. hydrolysis of dinitriles: Special methods: Oxalic acid: 1.Heating sodium formate: 2. By passing dry CO2 over sodium metal heated to 360° 3. By the oxidation of sucrose with conc. HNO3 in the presence of V2O5. Malonic acid: Preparation of diethylmalonate: Diethylamalonate is much more important than the acid. Succinic acid can also be prepared by reduction of malic and tartaric acids with HI and red P. Glutaric acid: 1. By the action of methylene iodide on ethylmalonate. 2. Oxidative fission of cyclopentanone with nitric acid in the presence of V2O5. Adipic acid: 1.Catalytic air oxidation of cyclohexane obtained from petroleum. 2. Oxidative fission of cyclohexanol or cyclohexanone by nitric acid at 30-40°. Phthalic acid:Is prepared by the catalytic oxidation of naphthalene or o-xylene Reactions: 1.Dicarboxylic acids show the same characteristic reactions as monocarboxylic acids. 2. Effect of heat b) Malonic acid : acids of the type where X is strongly electron attracting (e.g. –COOH, -CONH2, -COOR, -COR, -CHO, -CN, -NO2) lose CO2 even on mild heating. (C) Succinic and glutaric acids yield the corresponding cyclic anhydrides. Heating adipic acid with Ba(OH)2, MnCO3 or the O2 give cyclopentanone. (e) Phthalic acid form phthalic anhydride on heating at 200° Unsaturated and substituted acids Nomenclature: Ordinary methods of nomenclature can be applied to substituted acids, but many acids have trival names. Preparation: 1.Maleic acid: (a) Rapid heating of malic acid to about 250°. (b) Catalytic air oxidation of benzene at 400°. (c) Air oxidation of crotonaldehyde. 2. Fumaric acid and malic acid: 3. Tartaric acid: )1( Cyanohydrin synthesis from glyoxal : (2) from dibromosuccinic acid (3) Oxidation of maleic acid with neutral KMnO4 4. Citric acid: 1- From 1,3-dichloroacetone: 1,3-Dichloroacetone can be prepared by treating glycerol with HCl followed by oxidation. Reactions: 1- Addition of HX to α,β-unsaturated acids give β-haloacids. 2- Diels-Alder Reaction. 3- Heating tartaric acid gives pyruvic acid. 4- Heating citric acid to 175oC gives aconitic acid. 5. Reduction of tartaric acid with HI. 6- Citric acid loses water and CO on treatment with H2SO4 giving acetone dicarboxylic acid which on strong heating decomposes into acetone and CO2. Preparation of urea: 1. Urea may be obtained by the action of ammonia on ethyl carbonate of phosgene 2- Partial hydrolysis of cyanamide with dilute H2SO4 at 70. 3- Reactions of urea: 1- Urea is a very weak base. By accepting a proton on the oxygen atom, urea forms a positive ion which is stabilized by resonance. 2- Hydrolysis: urea undergo hydrolysis in acid or alkaline solutions or in water in the presence of the enzyme urease present in soya beans. 3. Reaction with nitrous acid 4. reaction with acid chlorides 5- Reaction with hypobromite. 6- Reaction with malonic ester (Synthesis of barbituric acid). Barbital, 5, 5-diethylbarbituric acid, is hypnotic. For their synthesis a disubstituted malonic ester is condensed with urea.