Alcohols, Phenols and Ethers - Physical and chemical properties

The boiling points of alcohols and phenols are significantly higher than those of hydrocarbons, ethers, and haloalkanes of comparable molecular masses due to the presence of intermolecular $H$-bonding.

Solubility of alcohols in water decreases with the increase in the size of the alkyl or aryl group because the non-polar hydrophobic part dominates.

Phenols are more acidic than alcohols because the phenoxide ion ($C_6H_5O^-$) is stabilized by resonance, whereas the alkoxide ion ($R-O^-$) is destabilized by the $+I$ effect of the alkyl group.

The Lucas Test distinguishes $1^\circ, 2^\circ,$ and $3^\circ$ alcohols using anhydrous $ZnCl_2$ and conc. $HCl$. $3^\circ$ alcohols give immediate turbidity, $2^\circ$ within 5 minutes, and $1^\circ$ only upon heating.

The Reimer-Tiemann reaction involves the treatment of phenol with chloroform ($CHCl_3$) in the presence of sodium hydroxide to introduce an aldehyde group at the ortho position, forming Salicylaldehyde.

Kolbe's Reaction involves the treatment of phenoxide ion with $CO_2$ followed by acidification to produce Salicylic acid (2-hydroxybenzoic acid).

Ethers have lower boiling points than isomeric alcohols because they cannot form intermolecular $H$-bonding with themselves.

Cleavage of ethers by hydrohalic acids ($HX$): Simple ethers react via $S_N2$ mechanism, where the halide ion attacks the smaller alkyl group. However, if a $3^\circ$ alkyl group is present, the reaction proceeds via $S_N1$ mechanism.