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Derivative of carboxylic acids (1) Acid halide. Nomenclature. باستبدال حرف e من اسم alkane بـ oyl halide. alkanoyl halide Alkane. - أو من اسم الحمض باستبدال ic بـ yl chloride. Preparations. Chemical reactions. Reaction of acid chloride with R-MgX. Hell volhard zelinski.
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Derivative of carboxylic acids (1) Acid halide Nomenclature • باستبدال حرف e من اسمalkane بـ oyl halide alkanoyl halideAlkane - أو من اسم الحمض باستبدالic بـ yl chloride
Preparations Chemical reactions
Reaction of acid chloride with R-MgX Hell volhard zelinski • Acid anhydride (2)
التسمية تتم بذكر اسم الحمض متبوعاً بكلمــة anhydride Preparation ( 1 ) From acid chloride
From acetylene (2) From ketene(3)
Chemical reactions Amide (3) • التسمية تتم بذكر اسمalkane محذوفاً منه حرف eواستبداله بـ amideأو اسم الحمض محذوفاً منه oicواستبدالها بـamide
Preparation of amides From acid chloride, anhydride, ester (1) From nitriles (2)
From ammonium salt ( 3 ) Chemical reactions Hydrolysis ( 1 ) Hofmann degradation of amide( 2 )
Q. Convert acetic acid to methyl amine الإجابـة Dehydration ( 3 ) ( 4 ) Action of nitrous acid
Esters (4) - التسمية تتم كالآتي:- 1- ذكر اسمR` 2- ذكر اسم الحمض محذوفاً منه-icومضافاً اليهate
Ortho ester Fats esters e.g.
Reactions of esters Reaction with Grignard to form t-alc
Mechanism Claisen condensation of ester
Substituted products of monocyclic acids 1. Halogenated acids تقسم الى α ، β ، γ ،δ على حسب موقع الهالوجين. Preparation of α-halo acid • Hell-Volhard-Zelinski reaction
Iodo derivative can be prepared as follow 2. From α-hydroxy acid preparation of β-halogenated acid • لاحظ الإضافة تتم عكس قاعدة ماركنكوف في حاله اتصال سلسله alkene • بمجموعهالدهيد أو كيتونأو -COOH
2. From hydroxy acid Preparation of γ-Halogenated acid Reactions of Halogenated acid Effect of NaOH on Halogenated acids 1. Effect of NaOH on α-Halo acid 2. Effect of NaOH on β -Halo acid
3. Effect of NaOH on γ – and δ-Halo acid (B) Hydroxy acids - تقسم الى α ، β ، γ ،δ على حسب موقع OH - أسماء يجب حفظها
Preparation of Hydroxyacids 1) Preparation ofα-hydroxy acid • From halogenated acid • 2. From aldehyde or ketones
2) Preparation of β-hydroxy acid Reformatsky reaction 3)Preparation of γ & δ-hydroxy acids
Chemical reactions • 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 group and basic group –NH2 , thus it is present in an inner salt (B) which is called Zeitter ion 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:- • oxidation of glycols: 2. hydrolysis of dinitriles:
Special methods: Oxalic acid: • 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: • By the action of methylene iodide on ethylmalonate.
2. Oxidative fission of cyclopentanone with nitric acid in the presence of V2O5. Adipic acid: • 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: • Dicarboxylic acids show the same characteristic reactions • as monocarboxylic acids. 2. Effect of heat acids of the type :b) Malonic acid 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: • 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: : Cyanohydrin synthesis from glyoxal (1) (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.
3- Heating tartaric acid gives pyruvic acid. 4- Heating citric acid to 175oC gives aconitic acid.