Commercial ethanol is obtained through fermentation, typically from sugars found in molasses, sugarcane, or fruits such as grapes. The sugars undergo conversion to glucose and fructose, followed by fermentation in the presence of yeast-derived enzyme zymase.
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Oxidation of phenol with chromic acid produces benzoquinone. In the presence of air, phenols undergo slow oxidation, forming dark-colored mixtures containing quinones.
Heating phenol with zinc dust leads to the conversion of phenol to benzene. Zinc acts as a reducing agent, facilitating this transformation.
The Reimer-Tiemann reaction involves treating phenol with chloroform in the presence of sodium hydroxide, resulting in the introduction of a -CHO group at the ortho position of the benzene ring. The intermediate benzal chloride is hydrolyzed to produce salicylaldehyde.
Methanol is mainly produced through the catalytic hydrogenation of carbon monoxide, utilizing a ZnO – Cr₂O₃ catalyst. It is used as a solvent in paints, varnishes, and predominantly in the production of formaldehyde.
Phenoxide ion, produced by treating phenol with sodium hydroxide, undergoes electrophilic substitution with carbon dioxide in Kolbe’s reaction, forming ortho hydroxybenzoic acid as the main product. The phenoxide ion is more reactive than phenol due to its enhanced nucleophilicity.
Phenol forms 2,4,6-tribromophenol as a white precipitate when treated with bromine water. This occurs under typical conditions, such as room temperature, favoring the formation of the tribromophenol product.
The -OH group in phenol activates the benzene ring, allowing halogenation to occur at low temperatures in solvents like CHCl₃ or CS₂, forming monobromophenols. Phenol’s high reactivity is attributed to the activating effect of the -OH group, eliminating the need ...
Picric acid is obtained by treating phenol first with concentrated sulfuric acid, converting it to phenol-2,4-disulphonic acid, and then with concentrated nitric acid to yield 2,4,6-trinitrophenol. The modern method is preferred for improved yield in the preparation of picric acid.
Phenol reacts with dilute nitric acid at low temperature, producing a mixture of ortho and para nitrophenols. Steam distillation is used to separate the isomers; o-nitrophenol is steam volatile due to intramolecular hydrogen bonding, while p-nitrophenol is less volatile due ...