Добавил:

ivanov666 Опубликованный материал нарушает ваши авторские права? Сообщите нам.

Вуз:

Башкирский Государственный Аграрный Университет

Предмет:

[НЕСОРТИРОВАННОЕ]

Файл:

Органическая химия = Organic Chemistry. Лабораторный практикум

.pdf

Скачиваний:

Добавлен:

09.08.2026

Размер:

426 Кб

Скачать

☆

<<< < Предыдущая 1 23 / 43 4 > Следующая >>>

Chemical properties

		OH					OH
		R-C-R' + Mg(OH)Br					R-C-R'
		CH3					OCH3
		alcohol CH MgBr					semiacetal
			3					OH
			H2O	CH OH				OH
			H2O	CH OH
	OH			3		H+		R-C-R'
	OH						HC N	R-C-R'
R-C-R'			HSO3Na	+			HC N	CN
R-C-R'			HSO3Na	+			-	CN
	SO3Na			R-C-R'			OH	cyanohydrin
sulphonate
sulphonate				O-			NH2NH2
derivative				O-			NH2NH2
		NH2NHC6H5			NH2OH		H+	R-C-R'
		NH2NHC6H5					H+
			H+
R-C-R'					H+
									NNH2
									NNH2
								hydrozone
NNHC6H6				R-C-R'				hydrozone
NNHC6H6				R-C-R'

phenylhydrozone
	NOH
	oxime

Carbonyl group is polarized since oxygen atom is more electronegative than carbon atom. So, carbon atom acquires a partial positive charge and oxygen atom acquires partial negative charge.

All the reactions of aldehydes and ketones can be divided into the following groups:

Nucleophilic addition

Condensation reactions

Reduction

Oxidation

Oxidation reactions

Ag(NH ) OH

Ag(NH3)2OH

3 2

H3C

+ Ag

Tollen's reagent

special

Tollen's reagent

H3C C

H3C

reactions

Cu+2/ solution

CH3

H3C

+ Cu2O

Ferling's reagent

Haloform reaction (exc. I2 , Cl2 or Br2, NaОН (conc.)

Haloform reaction is a special reaction for the acetyl moiety (СН3СО) in carbonyl compounds. In the case of reactions with iodine and bromine the stained precipitate with specific odor is smelled.

3 I2

CH3 C

HCI3

H-C

C-CH -CH

HCI3

CH3-CH2-C

ONa

NaOH(conc.)

ONa

iodoform

sodium formate

iodoform

sodium propanoate

Laboratory work №5.		Aldehydes. Ketones
№	Procedure		Equations of reactions	Observations
Exp

1Oxidation of aldehydes and ketones with

Tollen’s reagent (“Silver mirror”):			O Ag(NH3)2OH
Take two test tubes.	H	C
	H	C
			H
Into the first test tube place about 2 ml of			H
Into the first test tube place about 2 ml of
formalin (40% solution of formaldehyde
in water), into the second test tube place				O Ag(NH3)2OH
about 1 ml of acetone.	H3C			C
about 1 ml of acetone.	H3C			C
Into both test tubes add about 1 ml of				CH3
ammonium solution of silver oxide
(Tollen’s reagent Ag(NH3)2).

Not shaking the test tubes put them into a steam bath for 5 minutes.

2	Oxidation of aldehydes and ketones with
	Felling’s reagent (“Copper mirror”):			O		CuO
	Take two test tubes.	H	C
		H	C
				H
	Into the first test tube place about 2 ml of			H
	Into the first test tube place about 2 ml of
	formalin, into the second test tube place
	about 1 ml of acetone.				O	CuO
	Into both test tubes add about 1 ml of	H3C			C
	Into both test tubes add about 1 ml of	H3C			C
	Felling’s reagent.				CH3
	Felling’s reagent.
	Not shaking the test tubes put them into a
	steam bath for 5 minutes.

3Preparation of iodoform from acetone:

Place about 1 ml of acetone into a test

tube.

+ HI

NaOH

To the test tube add 2 ml of water.

H3C

C I

Then into the same test tube add several

CH3

crystals of iodine.

Add about 5 drops of concentrated sodium hydroxide.

Shake the obtained mixture and pay your attention to the formation of the yellow precipitate.

4 Preparation of bisulphate derivative of		O NaHSO3
acetone:		O NaHSO3
Place about 3 ml of acetone into a test	H3C	C
Place about 3 ml of acetone into a test	H3C	C
tube.		CH3
tube.

Into the same test tube add 1 ml of saturated sodium bisulphate solution (NaHSO3).

Shake the obtained mixture and cool it down.

Add about 5 drops of concentrated sodium hydroxide.

The formation of white precipitate is observed.


5	Preparations of phenylhydrozines:	O		NHNH2
5	Preparations of phenylhydrozines:
	Take two test tubes.		H +


	Place about 1 ml of benzaldehyde into the
	Place about 1 ml of benzaldehyde into the		O2N	NO2
	first test tube, into the second test tube –		O2N	NO2
	first test tube, into the second test tube –
	about 1 ml of acetone.

Into the each test tube add about 2 ml of

2%	solution	of	2,4-	H3C	O	+	NHNH2
dinitrophenylhydrozine.

					CH3
The test tubes put into a steam bath for 5					CH3	O2N	NO2
minutes, then cool them down.
Precipitates are observed.

CARBOXYLIC ACIDS

Organic compounds which contain the carboxyl group (COOH) are called carboxylic acids.

Nomenclature: The name of an acid is obtained by replacing the ending -e common names are usually used for most of the acids, since they are widely the source of them.

from the corresponding alkane by -oic acid. The spread in the nature and the common names show

H-C O	methanoic acid			CH3-CH2-CH2-C		O	butanoic acid	HOOC-COOH	ethandioic acid
H-C O	methanoic acid			CH3-CH2-CH2-C			butanoic acid		oxalic acid
OH	formic acid					OH butyric acid		HOOC-CH2-COOH		propandioic acid
CH3-C O				CH -CH-C O				HOOC-CH2-COOH		malonic acid
CH3-C O		ethanoic acid		CH -CH-C O		2-methylpropanoic acid		HOOC-(CH ) -COOH		butandioic acid
OH		acetic acid		3	OH			HOOC-(CH ) -COOH		succinic acid
OH		acetic acid		CH3	OH			2 2		succinic acid
								2 2
CH3-CH2-C		O	propanoic acid					C17H33COOH , CH3(CH2)7 CH=CH (CH2)7COOH
CH3-CH2-C		OH	propionic acid					oleic acid
								C17H35COOH	stearic acid

The main chemical properties of carboxylic acids can be divided into three groups:

Reaction involving the –OH group (acidic properties);

Nucleophilic substitution at the carbon atom of carboxylic group;

Substitution of the hydrogen atom at the carbon atom in α-position and reduction.

		R-C
	200°C	ONH4
	200°C	ammonium salt
		ammonium salt

NH3

+ H2O

O + R-C

20 °C

KOH

R-C

NH2

NH3

amide

R'-OH

salt of carboxylic acid

P O

R-C

+ H2O

2 5

OR'

R-CN + H3PO4

PCl5

P2O5

ester

nitrile

(SOCl2)

R-C O

O + H3PO4

R-C

+ POCl

+ HCl

Cl ( SO23

+ HCl )

anhydride

alkanoyl halide

Laboratory work №6.	Carboxylic acids
№	Procedure	Equations of reactions	Observations
Exp

1Extraction of fatty acids from soap and

preparation of calcium salts:

+H2SO4

Take two test tubes.

C17H35

Place about 3 ml of aqueous soap solution

ONa

tubes.

into the test

Into the first test tube add 1 ml of dilute

sulfuric acid.

+ CaCl2

Heat the obtained mixture and then cool it to

ONa

the room temperature. On heating fatty acids

risetothesurfacebutoncoolingtheybecome

solid.

Into the second test tube add 1 ml of calcium chloride solution. The formation of calcium salt of fatty acids as white precipitate occurs.

2Unsaturated acids. Preparation of salt of oleic

acid and oxidation of oleic acid:

CH3-(CH2)7-CH=CH-(CH2)7

+ NaOH

Take from the laboratory assistant oleic acid

and divide its amount into two test tubes.

Into the first test tube add about 2 ml of water

(pay your attention that oleic acids is not

soluble in water). Then add 2 ml of sodium

hydroxide and shake the test tube.

Into the second test tube with oleic acid add

1 ml of KMnO4. Shake the obtained mixture

-(CH )

-CH=CH-(CH )

+ KMnO4

vigorously. The KMnO4 solution is

2 7

decolorized since oleic acid contains the

double bond.

Preparations of esters:

H2SO4

Take two test tubes.

Place about 2 ml of concentrated acetic acid

H3C

+ C2H5OH

into the two test tubes.

Into the first test tube add 2 ml of ethanol and

several drops of concentrated sulfuric acid.

Then heat the obtained mixture in a steam

bath for 2 minutes.

Into the second test tube add 2 ml of isoamyl

H3C

H2SO4

alcohol (2-methylbutanol-1) and several

H3C

CH CH2-CH2-OH

drops of concentrated sulfuric acid. Then

H3C

heat the obtained mixture in a steam bath for

5 minutes.

Into the both test tubes add same water, the

formed esters rise to the surface. Esters have

pleasant smell.

CARBOHYDRATES

Carbohydrates are a major class of naturally occurring organic compounds, which come by their name because they have, or approximate, the general formula Сn(H2O)n. These include glucose (grape sugar), fructose (honey), sucrose (cane sugar), starch (potatoes), and cellulose (wood).Although the structures of many carbohydrates appear to be quite complex, the chemistry of these substances usually involves only two functional groups- ketone or aldehyde carbonyls and alcohol hydroxyl groups.

aldohexose

ketohexose

CHO

CH2OH

D-glucose

D-galactose

D-mannose

D-fructose

Glucose forms a stable cyclic hemiacetal between the CHO group and the OH group on the fifth carbon atom. In this process the first carbon (С1) atom becomes asymmetric, giving two isomers (α-D-glucose and β-D-glucose) which differ in the configuration of the asymmetric carbon atom.

Crystalline monosaccharides exist in cyclic forms but when they are dissolved in water they undergo equilibration to the mixture of cyclic and chain forms. The open-chain form is an intermediate in this process. All tautomeric forms permanently convert into one another; this process is called ring-chain tautomerism.

O H

OH O

-D-glucose

D-glucose (oxo-form)

-D-glucose

Glucose undergoes all the reactions which are typical for aldehydes and alcohols. Depending on the type of the reagent monosaccharides react via the chain or cyclic form.

<<< < Предыдущая 1 23 / 43 4 > Следующая >>>

Соседние файлы в предмете [НЕСОРТИРОВАННОЕ]