what is Caffeine: Uses, Properties, Isolation, synthesis

What is Caffeine?

Caffeine.

Caffeine is one of the most popular drinks in the world, and is considered by many as morning fuel, as these drinks have become an important part of daily life in individuals, especially workers and students. Where many consider them the main reason for their stay awake and also the main reason For their activity throughout the day. It is an important member of the class and has the structure.
Caffeine structure.
Caffeine occurs in dried tea leaves (up to 5%), coffee beans (up to 2%), and in cola leaves (up to 2.5%). It is a mild stimulant to the central nervous system and a nitrogen heterocyclic compound. Thus, it is now termed an alkaloid.

Isolation from Waste Tea.

The damaged leaves and stem of the tea plant are boiled with water and filtered. The filtrate containing caffeine, proteins, and tannins is treated with basic lead acetate. The proteins and tannins get precipitated and are filtered off. To the filtrate is then added dilute sulphuric acid to remove any excess of lead acetate as insoluble lead sulphate. The resulting solution is decolourised with animal charcoal and caffeine extracted from it with chloroform. Chloroform is distilled off and the residue of crude caffeine is recrystallized from water to get the pure product.

Synthesis from Uric acid (Fischer, 1899).

Uric acid is treated with methyl iodide in alkaline solution to give 1,3,7-trimethyluric acid. This on heating with phosphoryl chloride (POCl3), forms chlorocaffeine which on reduction with hydrogen iodide yields caffeine.
Synthesis from Uric acid (Fischer, 1899).
Synthesis from Uric acid (Fischer, 1899).

Caffeine Properties.

Caffeine crystallises in beautiful colourless needles with one molecule of water of crystallisation. The anhydrous compound melts at 238°C. It has a feeble bitter taste and is sparingly soluble in water and organic solvents, being insoluble in ether. It is a weak base and forms salts with strong acids.


Caffeine is a mild stimulant to the central nervous system, the heart and the respiratory system.That is why we feel refreshed when we take tea, coffee, or cola soft drinks. Caffeine is used in non-prescription stimulants and sleep-preventing pills. It is a diuretic.

Caffeine Uses.

Caffeine found in coffee, tea, cola and other other products. Caffeine is widely used to improve mental alertness and other uses. The recommended amount of caffeine is usually 400 milligrams per day for healthy adults, and adolescents should not exceed 100 mg of caffeine per day. Pregnant women may not take more than 200 milligrams per day of caffeine. However, taking high doses of caffeine may have bad side effects and even dangerous, drinking more than three cups of coffee or two packs of energy drink per day will lead to collateral damage.

Caffeine Sources.

Coffee, black tea, red bean, Soda, dark chocolate bars, sweets, medicines and supplements, and any energy-enhancing food product.
what is Caffeine: Uses, Properties, Isolation, synthesis what is Caffeine: Uses, Properties, Isolation, synthesis Reviewed by Genuine Chemistry on June 07, 2019 Rating: 5

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