Acetic Acid → 6-Chloromethyl-1,1,4,4,7-pentamethyl-5-methoxy-1,2,3,4-tetrahydronaphthalene

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Reaction Conditions

Reaction Steps

To prepare the corresponding 6-carboxaldehyde, 6-formyl-1,1,4,4,7-pentamethyl-5-methoxy-1,2,3,4-tetrahydronaphthalene, 1,1,4,4,7-pentamethyl-5-methoxy-1,2,3,4-tetrahydronaphthalene (23.2 g, 0.1 mol) is added to a stirred solution of acetic acid (18.2 g, 0.3 mol), 85% phosphoric acid (17.6 g, 0.15 mol), hydrochloric acid (28.7 g, 0.3 mol) and paraformaldehyde (7.3 g, 0.24 mol). The mixture is stirred and heated at 95° C. for 16 hr. The reaction mixture is then cooled to 25° C., benzene (50 ml) added, and stirred vigorously. The organic layer is separated, washed with water (2×25 ml), neutralized with 5% sodium bicarbonate solution, and dried (Na2SO4). The solvent is removed by distillation to provide 6-chloromethyl-1,1,4,4,7-pentamethyl-5-methoxy-1,2,3,4-tetrahydronaphthalene.

Provenance & Evidence