Dehydrogenation of alcohol using Cu

Reactions of Alkoxides

Klobe's reaction

Phenoxide ion generated by treating phenol with sodium hydroxide is even more reactive than phenol towards electrophilic aromatic substitution. Hence, it undergoes electrophilic substitution with carbon dioxide, a weak electrophile. Ortho hydroxybenzoic acid is formed as the main reaction product.

Heating the nucleophilic phenolate salt with carbon dioxide under high pressure / temperature results in regioselective ortho-substitution.
This process is also known as the Kolbe-Schmitt synthesis.
o-hydroxybenzoic acid is more commonly known as salicyclic acid.

Reimer-Tiemann reaction

On treating phenol with chloroform in the presence of sodium hydroxide, a –CHO group is introduced at ortho position of benzene ring. This reaction is known as Reimer - Tiemann reaction. The intermediate substituted benzal chloride is hydrolysed in the presence of alkali to produce salicylaldehyde.

Hydroboration-oxidation

Write the main product in the following reactions.