Nitric Acid → 2,2,6-Trimethylcyclohexanecarboxylic acid

Participants

Reaction Conditions

Reaction Steps

In a 300-ml 4-necked flask equipped with a condenser, a thermometer, a dropping funnel, and a stirrer was placed 40 g of nitric acid (60% aqueous solution) and heated to 55° C. To the solution was added dropwise 95 g (0.62 mole) of 2,2,6-trimethylcyclohexanecarbaldehyde (4) composed of 90% of the trans-form and 10% of the cis-form synthesized in Synthesis Example 2-A) described above over a period of 2 hours. Thereafter, the reaction was carried out for 3 hours at the same temperature. Then, 100 g of toluene and 100 g of water were added to the reaction mixture at room temperature to wash with water and form an organic layer and an aqueous layer separately. The organic layer was washed thrice with 100 g of a saturated aqueous sodium chloride solution, and 80 ml of the toluene was distilled off under reduced pressure by means of an evaporator, to provide 104 g of crude 2,2,6-trimethylcyclohexanecarboxylic acid (5) composed of 89% of the trans-form and 11% of the cis-form (boiling point: 44° to 54° C.). The mass spectra of the cis- and trans-forms of the acid (5) were the same as those in Synthesis Example 1.

Provenance & Evidence