R2CHOH

R2CHOH denotes a secondary alcohol in which the carbon bearing the hydroxyl group is attached to two identical substituents, R, and one hydrogen. The general formula thus describes homo-substituted secondary alcohols. When R equals a methyl group, the compound is isopropanol (isopropyl alcohol), a common solvent and disinfectant. The broader class with two potentially different substituents is sometimes written as R1R2CHOH; in that case, the molecule may be chiral if R1 and R2 are different.

Structure and stereochemistry: In R2CHOH with identical substituents, the carbon center is not a stereocenter. If R1 ≠ R2 (for R1R2CHOH), the carbon can be chiral, leading to enantiomeric forms in many cases.

Preparation and occurrence: Most secondary alcohols can be prepared by reducing the corresponding ketone (R2C=O) with hydride reagents such as NaBH4 or LiAlH4, or by catalytic hydrogenation of the ketone. Isopropanol is industrially produced by hydrogenating acetone. Secondary alcohols occur widely in nature and in many chemical syntheses as intermediates, solvents, and building blocks for pharmaceuticals, fragrances, and polymers.

Physical properties: Secondary alcohols typically have higher boiling points than alkanes of similar molecular weight due to hydrogen bonding, and they are generally less volatile than primary alcohols of the same size. Solubility in water decreases as the hydrophobic R groups grow larger.

Reactions: Common transformations include oxidation to ketones (R2C=O), dehydration under acid to yield alkenes, and substitution with hydrogen halides to form alkyl halides. Chiral secondary alcohols can be resolved to individual enantiomers.

Applications: Isopropanol is a widely used solvent, disinfectant, and cleaning agent. More broadly, R2CHOH compounds serve as important intermediates in organic synthesis and industrial chemistry.