1

PRACTICAL OF ORGANIC CHEMISTRY

SYNTHESIZE ORGANIC COMPOUNDS

Prepared by:

MUHAMMAD REZA (1106103040017/2011)

ABDUL MUJALA (1106103040021/2011)

NUZULIA (1106103040004/2011)

MELVI FADILLAH (1106103040028/2011)

TEACHER TRAINING AND EDUCATION FACULTY

SYIAH KUALA UNIVERSITY

BANDA ACEH

2013

3

CHAPTER I

INTRODUCTION

1.1 Background

In the development of organic chemistry, the need for various types of

organic compounds will certainly increase. This need drives the desire to get a

variety of organic compounds for the purposes of research, teaching or activity in

laboratory experiments. This is one of the indicators for doing synthesis in the

laboratory work.

The synthesis of organic compounds classified as more difficult than the

synthesis of inorganic compounds. Temperature and reaction time also affect the

amount of product produced by prolonging the reaction time and reaction

temperature regulate the products produced, the better (Ngadiwiyana, 2007). This

suggests that the synthesis of organic compounds needed special treatment by

setting the temperature and time options.

The success of the synthesis has been growing rapidly for several

branches of science in the field of organic. To get a lot of compounds in a short

period of time that is efficient and relatively easy. Needs of the laboratory

practicum course increasingly met with the synthesis models.

Synthesis activity was initially influenced by the limitations of the

available chemical compounds, thus encouraging researchers to process the

chemicals are available in large numbers. A chemical compound is converted into

another compound forms simply by reacting with certain reagents. This success

makes the synthesis of theory is growing and widely used in learning.

4

The synthesis of organic compounds can be done by total synthesis or

partial synthesis. Total synthesis is an overall change of a substance into other

compounds with structural changes. While synthesis is only partially accompanied

by changes in some physical properties of the compound to be synthesized. For

example, the synthesis of compounds with functional group changes or changes in

the structure of the bond.

Synthesis of compounds with functional groups or a change in bonding

structure changes require only a few treatments. Such as temperature, pressure,

and catalysts as well as the appropriate reagents. When chosen process is correct,

then the synthesis reaction will run easly.

For example in the synthesis of ketones using alcohol. This treatment

seeks to transform into a ketone functional group alcohol functional group. By

using appropriate reagents and heating, the reaction will proceed rapidly and form

the desired product.

Based on this background, the practicans wants to demonstrate and prove

the success of the synthesis theory in laboratory experiments. Synthesis will be

performed to alkenes, ketones and esters by using alcohol for synthesis of alkenes

and ketones and esters for the synthesis of salicylic acid.

1.2 Problem Statements

Based on the background of the problem, formulation of the problem can

be formulated as follows:

1) What is the effect of varying the organic reaction to the synthesis of

organic compounds?

5

2) Is the organic compound can be purified by means of synthesis?

1.3 Study Objective

Based on the above formulation of the problem, the purpose of this

experiment is to:

1) Skilful to synthesize organic compounds based on various organic

reactions.

2) Skilful purifying of organic compounds synthesize.

1.4 Benefits of Experiment

1) Benefits of Theoritical

Theoretically, this experiment to prove the truth of the theory of

synthesis have been developed by many scientists. In addition to laboratory work

to facilitate learning process to synthesis of organic compounds.

2) Applicative Benefits

Based on the applicative, in this experiment to get the best practices in

doing organic compounds synthesis. In addition, to determine the abundance of

organic compounds obtained by the synthesis of chemical functional groups of

adjacent structures and bindings.

6

CHAPTER II

LITERATURE

2.1 Dehydration of Alcohols

Propene (known industrially by its older name propylene) is not far

behind, ranking ninth in all industrially produced chemicals, with an annual U.S.

output of more than 22 billion pounds. The major uses of propene are the

production of polypropylene. Propene is a key compound in the production of

phenol, which is used in adhesives, and acetone, a commercially important

solvent, (Loudon, 1995).

In dehydration of alcohols, the H and OH are lost from adjacent carbon.

An acid cataliyst is necessary. Before dehydrogenation of ethane became the

dominant method, ethylene was prepared by heating ethyl alcohol with sulfuric

acid. Other alcohols behave similarly. Secondary alcohols undergo elimination at

lower temperatures than primary alcohols. And tertiary alcohol dehydrate at lower

temperatures than secondary alcohols. Sulfuric acid (H2SO4) and phosphoric acid

(H3PO4) are the acid most frquently used in alcohol dehydrations. Potassium

hydrogen sulfate (KHSO4) is also often used (Carey, 2006).

The mechanism of alkene formation under these conditions is andoubtedly

complex. At high temperature and with strong acid catalysts, the alcohol and the

corresponding ether are in equilibrium with one another. The eliminiation process

itself is probably of the E2 type in which a base attacks a protonated alcohol or

protonated ether. The base invoved may be bisulfate ion, HSO4-, or an alcohol or

ether molecule. n-propyl alcohol may be similarly dehydrated to propene. For

7

primary alcohols larger than propyl, mixtures of alkenes result ( Streitwieser,

1973).

For 4-methyl-2-pentanol dehydration, ZrO2SiO2 mixed xerogel and

aerogel catalysts resulted into lower conversion (435%); sulfated xerogel

samples showed higher conversion and selectivity for 4-methyl-1-pentene

compared to sulfated aerogel samples. The correlation of 4-methyl-2-pentanol

conversion with acid site density and sulfur per unit area was found to be linear,

which suggested that higher surface acidity is required to achieve significant

conversion of 4-methyl-2-pentanol as well as for higher selectivity for the desired

product, i.e., 4-methyl-1-pentene (Sidhpuria, Tyagi, and Jasra).

2.2 Preparation of Ketone

In general, aldehydes and ketones have higher boiling point than alkenes

because they are more polar and the diplole-dipole attractive forces between

molecules are stronger. But they have lower boiling points than alcohols because,

unlike alcohols, two carbonyl groups cant form hydrogen bonds to each other.

The carbonyl oxygen of aldehydes and ketones can form hydrogen bonds with the

protons of OH groups. This makes them more soluble in water then alkenes, but

less soluble than alcohols (Carey, 2006).

Secondary alcohol can be oxidized to ketones. The reaction usually stop at

the ketone stage beucause further oxidation requires the breaking of a carbon-

carbon bond. Various oxidizing agents based on chromium (VI) have been used to

oxidize secondary alcohols to ketones. The most commonly used reagent is

8

chromic acid (H2CrO4). As chromic acid oxidizes the alcohols to the ketones,

chromium is reduced from the +6 oxidation state (H2CrO4) to the +3 oxidation

state (Cr3+

). Chromic acid oxidations of secondary alcohols generally give ketones

in excellent yields if the temperature is controlled (Graham and Craig, 1998).

Oxidation of secondary alcohols to ketones, many oxidizing agents are

available for converting secondary alcohols to ketones. PDC or PCC may be used,

as well as other Cr(VI)-based agents such as chromic acid or potassium

dichromate and sulfuric acid (Carey, 2006).

Recall that the order of carbocation stability is secondary > primary >

methyl. The dipolar rensonance structure of formaldehyde is analogous to a

methyl cation, that for propionaldehyde is analogous to a primary carbocation, and

that for a ketone is analogous to a secondary carbocation. Just as isopropyl cation

is more stable than n-propyl, acetone is more stable than propionaldehyde owing

to the extra stabilization imparted by the dipolar rensonance structure

(Streitwieser, Heathcock and Kosower, 1992).

The metal-catalyzed synthesis of monoisopropylamine (MIPA) from 2-

propanol includes the dehydrogenation of the alcohol to acetone; condensation

with ammonia to form an imine, and hydrogenation to MIPA. Each intermediate

and the product amine can take part in various side reactions such as

condensation, decarbonylation, disproportionation, and hydrogenolysis. Proper

reaction conditions for the amination reaction can result in a primary amine as the

desired product in high yield, ( Cho, Park, Chang, Kim,and Shin, 2013).

9

2.3 Preparation Of Ester

Salicylates are non-steroid anti-inflammatory agents that are either esters

of organic acids (substitution at the hydroxyl group) or esters or salts (substitution

at the carboxyl group) derived from salicylic acid. The main derivatives of

salicylic acid are acetylsalicylic acid, methylsalicylate and salicylaldehyde.

Although, all three compounds are used in the pharmaceutical industry,

acetylsalicylic acid, i.e. Aspirin, is probably the most popular drug widely applied

throughout the world. (Papp, Simadi, Blazics, Alberti, Hethelyi, Szoke, and Kery,

2008).

2.4 Physical and Chemical Properties of 2-propanol

Physical and chemical properties of 2-propanol was taken from Material

Safety Data Sheet (MSDS) of Science Lab data as below:

Picture 2.1. MSDS of 2-propanol Science Lab

10

2.5 Physical and Chemical Properties of Salicylic Acid

Physical and chemical properties of 2-propanol was taken from Material

Safety Data Sheet (MSDS) of Science Lab data as below:

Picture 2.2 MSDS of Salicylic Acid Science Lab

11

CHAPTER III

DISCUSSION

3.1 Preparation of Propene from 2-propanol

Alkene hydrocarbon is a compound composed of carbon and hydrogen

elements with duplicate carbon chain. In experiment propene can be prepared by

synthesis. Synthesis is a method to obtain a compound of compound available. In

the synthesis of some commonly used reagents in a temperature and specific

circumstances to produce efficient products.

In this experiment, alkene synthesis performed by reacting alcohol with

concentrated sulfuric acid. Sulfuric acid (H2SO4) and phosphoric acid (H3PO4)

are the acid most frquently used in alcohol dehydrations. Potassium hydrogen

sulfate (KHSO4) is also often used (Carey, 2006). Thus, the selection of

concentrated sulfuric acid as pereaski in the synthesis of alkenes from alcohol is

very efficient, due to the presence of concentrated sulfuric acid can mendihidrasi

OH group in alcohol, thus alkene can be formed at the end of the reaction.

Synthesis propene in experiments using 2-propanol as considering the number of

carbon atoms in the compound. 2-propanol is reacted with concentrated sulfuric

acid for the dehydration of OH groups in the compound 2-propanol.

According to Clayton (1973) The mechanism of alkene formation under

these conditions is andoubtedly complex. At high temperature and with strong

acid catalysts, the alcohol and the corresponding ether are in equilibrium with one

another. The eliminiation process itself is probably of the E2 type in which a base

attacks a protonated alcohol or protonated ether. The base invoved may be

bisulfate ion, HSO4-, or an alcohol or ether molecule. n-propyl alcohol may be

12

similarly dehydrated to propene.For primary alcohols larger than propyl, mixtures

of alkenes result. Stages complex which causes the formation of propene results in

the synthesis reaction, in which the OH group urges complex of 2-propanol to

dehydrated.

To carry out the synthesis reaction of propene is used method of

distillation. Distillation is the separation of compounds from mixtures based on

differences in boiling point. Propene is formed from the condensation dehirasi

soon as the alcohol distilled and separated as distillate. To test the chemical

properties of the products, then propene dissolved in water and gasoline, it can be

observed that in the two solvents, soluble propene.

3.2 Preparation of Ketone from 2-propanol

Ketones are compounds commonly called down alkane hydrocarbon

derivatives. Called alkane derivatives because of the group H in alkanes

substituted with a carbonyl functional group is C = O. Carbonyl group mean is

there a binding carbon atoms other than H, which binds the carbon atoms in the

ketone oxygen atom (O) with a double bond. Just like alkenes, ketones can also be

synthesized from other compounds available in certain experimental purposes.

In this experiment, the synthesis of ketones from 2-propanol compound.

2-propanol is used, seeking acetone compound where the number of carbon atoms

of the two compounds is the same that is three carbon atoms. Synthesis is done by

reacting 2-propanol with distilled water and the addition of K2Cr2O7 as a catalyst.

The addition of the dichromate acid as a catalyst to accelerate the reaction goes to

get products more efficiently. The reaction carried out by means of distillation. In

general, aldehydes and ketones have higher boiling point than alkenes because

13

they are more polar and the diplole-dipole attractive forces between molecules are

stronger. But they have lower boiling points than alcohols because, unlike

alcohols, two carbonyl groups cant form hydrogen bonds to each other. The

carbonyl oxygen of aldehydes and ketones can form hydrogen bonds with the

protons of OH groups. This makes them more soluble in water then alkenes, but

less soluble than alcohols (Carey, 2006).

Reaction synthesis of ketones from alcohol can be classified into the type

of alcohol oxidation reaction. Oxidation of the secondary alcohol will produce

ketones when using catalyst K2Cr2O7 and chromic acid (K2CrO4). However, when

using the catalyst in addition to the two chromic acid, eg PCC (pyridinium chloro

chromate) will not form a ketone from a secondary alcohol as the PCC is the most

powerful oxidizer. According to Carey (2006) Oxidation of secondary alcohols to

ketones, many oxidizing agents are available for converting secondary alcohols to

ketones. PDC or PCC may be used, as well as other Cr(VI)-based agents such as

chromic acid or potassium dichromate and sulfuric acid. With PCC oxidant, the

primary alcohol can be directly converted into ketones as very high oxidation

power.

Secondary alcohol can be oxidized to ketones. The reaction usually stop

at the ketone stage beucause further oxidation requires the breaking of a carbon-

carbon bond. Acoording Solomons (1998) Various oxidizing agents based on

chromium (VI) have been used to oxidize secondary alcohols to ketones. The

most commonly used reagent is chromic acid (H2CrO4). As chromic acid oxidizes

the alcohols to the ketones, chromium is reduced from the +6 oxidation state

14

(H2CrO4) to the +3 oxidation state (Cr3+

). Chromic acid oxidations of secondary

alcohols generally give ketones in excellent yields if the temperature is controlled.

For the identification results of the experiment synthesis of ketones, used

two kinds of tests that chromic acid test and iodoform test. At this stage of the test

iodoform, iodoform reagent reacted with ketones and showed blue-green solution.

Next on stage chromic acid test, ketones reacted with chromic acid reagent

solution and shows like two layers of clouds. Both results show that the

identification of positive results of the synthesis of ketones.

3.3 Peparation Oil of Wintergreen

In addition to alcohol and ketones, there are other types of alkane

derivatives, namely esters with fungi group R-COO-R '. Esther possessed

semipolar nature and can form hydrogen bonds with water molecules, so that the

ester can be dissolved in water. Esther in the laboratory are often used as organic

solvent, although its use for less than the price of the ester alcohol is much more

expensive than alcohol. To get to do the synthesis of esters of carboxylic acids

with bases or alcohol.

For example, in an experiment to obtain oil of wintergreen (metal

salicylates) of salicylic acid. Mixture of salicylic acid with alcohol mixed metal

with the addition a few drops of concentrated sulfuric acid as a catalyst in the

reaction. According to Simadi (2008) Salicylates are non-steroid anti-

inflammatory agents that are either esters of organic acids (substitution at the

hydroxyl group) or esters or salts (substitution at the carboxyl group) derived from

salicylic acid. The main derivatives of salicylic acid are acetyl salicylic

acid,methyl salicylate and salicylaldehyde. Although, all three compounds are

15

used in the pharmaceutical industry, acetylsalicylicacid, i.e. aspirin, is probably

the most popular drug widely applie throughout the world.

A mixture of salicylic acid mixed with methanol and concentrated

sulfuric acid heated untu few moments to arise distinctive smell esters, usually

typical fragrant ester. This reaction is called the reaction Sintesi substitution

reaction, takes place in turn of several groups of two reagents which produce oil

of wintergreen (methylsalicylate) and water (H2O).

16

CHAPTER IV

CONCLUSIONS

Based on the previous discussion and the experimental results, it can be

concluded that:

1. Alkene synthesis performed by reacting alcohol with concentrated sulfuric

acid. Sulfuric acid (H2SO4) and phosphoric acid (H3PO4) are the most

frquently acid used in alcohol dehydrations. Potassium hydrogen sulfate

(KHSO4) is also Often used.

2. Stages complex which causes the formation of propene results in the

synthesis reaction, in which the OH group urges complex of 2-propanol to

dehydrated.

3. Reaction synthesis of ketones from alcohol can be classified into the type

of alcohol oxidation reaction. Oxidation of the secondary alcohol will

produce ketones when using catalyst K2Cr2O7 and chromic acid (K2CrO4).

4. Salicylates are non-steroid anti-inflammatory agents that are either esters

of organic acids (substitution at the hydroxyl group) or esters or salts

(substitution at the carboxyl group) derived from salicylic acid.

5. At this stage of the test iodoform, iodoform reagent reacted with ketones

and showed blue-green solution. Next on stage chromic acid test, ketones

reacted with chromic acid reagent solution and shows like two layers of

clouds.

6. Reaction Sintesi oil of wintergreen called substitution reaction, takes place

in turn of several groups of two reagents which produce oil of wintergreen

(methylsalicylate) and water (H2O).

17

REFFERENCES

Carey, Francis A. 2006. Organic Chemistry Sixth Edition. New York : Mc. Graw

Hill.

Cho, Jun Hee; Park, Jung-Hyun; Chang, Tae-Sun; Kim, Jin-Eok; and Shin, Chae-

Ho. 2013. Reductive Amination of 2-propanol to Monoisopropylamine

Over Ni/gamma-Al2O3 Catalysts. Catal Lett, Vol.143 : 1319- 1327.

Loudon, G.M. 1995. Organic Chemistry Third Edition. California : The Benja-

min/Cummings Publishing Company.

Papp, Ildiko; Simadi, Bela; Blazics, Balzs; Alberti, Agnes; hethelyi, Eva; Szoke,

Eva; and Kery, Agnes. 2008. Monitoring Volatile and Non-volatile

Salicylates in Filipendula Ulmaria by different Chromatographic

Techniques. Chromatographic Supplement, Vol.68 : S125-S129.

Sidphuria, Kalpesh B.; Tyagi, Beena; and Jasra,Raksh V. 2011. ZrO2- SiO2 Mixed

Oxides Xerogel and Aerogel as Solid Acid Catlysts for Solvent Free

Isomerization of alpa-Pinene and Dehydration of 4-methyl-2-pentanol.

Catal Lett, Vol.141 : 1164- 1170.

Solomons, Graham and Fryhle, Craig. 1998. Organic Chemistry Seventh Edition.

New York : John Wiley & Sons.

Streitwieser Jr, Andrew and Heathcock, Clayton H. 1973. Introduction to Organic

Chemistry. New York : Macmillan Publishing.

Streitwieser, Andrew; Heathcock, Clayton H; and Kosower, Edward M. 1992.

Introduction to Organic Chemistry Fourth Edition. New York :

Macmillan Publishing.

http://www.sciencelab.com/msds.php?msdsId=9927249, browsed on Wednesday,

1st of January 2014.

http://www.sciencelab.com/msds.php?msdsId=9924413, browsed on Wednesday,

1st of January 2014.

18

Attachment 1

Pre-practicum Observation Equipment

Name Amount Type of

Materials

Utility

Graduated

cylinders

2 units Glass Measured the

solutions

Stir 1 unit Glass Mix the mixture

Round bottom

flask

1 unit Glass Accommodate

solutions

Thermometer 1 unit Glass Measude the

temperature

Distillation Tools 1 unit Glass Separated the

mixture

Tripod 2 units Iron metal Mountings

container when

heating

Spiritus lamp 3 units Glass Burner

Kasa asbestos 2 units Wire and asbestos Mountings tool on

tripod

Tube 5 units Glass Reactors of

solutions

Beaker 2 units Glass Container

19

Attachment 2

Pre-practicum Material Observation

Name Formula Form Colour

2-propanol C3H8O Liquid No colour

Sulphuric acid

98%

H2SO4 Liquid No colour

Distiled water H2O Liquid No colour

Acidic dichromate K2Cr2O7 Solution Orange

Methyl alcohol CH3OH Liquid No colour

Salicylic acid C7H6O3 Solid White

20

Attachment 3

Observations at Experiments Process

1. Preparation of Propene (Dehydration of Alcohols)

No Part of Observed Phenomena of Observed

1 Mixture consist 2-

propanol, sulphuric

acid and distilled

water.

Distillation process will product the propene after

heating at 700C 800C.

2 Dissolved propene in

water

Propene soluble in water readily.

21

3 Disslove propene in

gasoline

Propene is insoluble in gasoline

2. Preparation of Ketone

No Part of Observed Phenomena of Observed

1 Preparation of acidic

dichromate solution

The colour of solution is orange

2 The mixture consist

2-propanol, distilled

water and acidic

chromate.

22

3 Separation process

to produce acetone.

4 Acetone that

produced as distillate

in erlenmeyer.

3. Prepataion of Ester as Oil of Wintergreen

No Part of Observed Phenomena of Observed

1 Salicylic acid +

sulphuric acid and

methyl alcohol

Salicylic acid less soluble without heating

2 The mixture was

heating to make

salicylic acid more

soluble

23

3 After heating, the

mixture have soluble

totality (oil of

wintergreen)

The colour of mixture is dark violet.

4 Oil of wintergreen +

distilled water

Oil of winter green is insoluble in water.

24

Attachment 4

Flow Chart of Experiments

Sythesize Organic Compounds

Preparation of propene

Sulphuricacid(22ml) + 2-

propanol(11.6ml) + distilled

water(20ml)

Distillation

Propene

Preparation of Acetone

2-propanol(14ml) + distilled water (26ml)+acidic

dichromate 0.1 M (100ml)

Distillation

Acetone

Oil of Wintergreen

Salicylic acid 0.2 grams +1ml of methyl

alcohol + 1ml of sulphuric acid 98%

Heating

Methyl salicylate

25