Reaction Steps
Formylation. 3-Ethyl-1-hydroxy-5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalene (94 g, 0.405 mol) was stirred with glacial acetic acid (670 mL), and hexamethylenetetramine (102.6 g, 0.73 mol) was added in one portion. The mixture was heated at 95° C. for 3 h, hot water (670 mL) added, and the heating was continued for an additional 1.5 h at 100° C. The mixture was cooled to 20° C., toluene (200 mL) was added, and the mixture was stirred vigorously. The organic layer was separated, washed with water (3×150 mL), then neutralized with 5% NaHCO3 solution, and finally washed with brine (50 mL). The solvent was evaporated and the residue distilled to give 3-ethyl-2-formyl-1-hydroxy-5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalene (77.9 g), bp 127°-132° C./0.5 mm, GLC purity 98%, 1H-NMR (CDCl3) δ12.87 (1H, s), 10.20 (1 H, s), 6.72 (1H, s), 2.89 (2H, q), 1.65 (4H, m), 1.44 (6H, s), 1.30 (3H, t), 1.29 (6H, s). 13C-NMR (CDCl3) δ194.3 (1C, d), 163.6 (1C, s), 156.7 (1C, s), 144.6 (1C, s), 130.8 (1C, s), 118.5 (1C, d), 115.2 (1C, s), 37.7 (1C, t), 35.5 (1C, s), 34.7 (1C, t), 34.0 (1C, s), 31.1 (2C, q), 27.7 (2C, q), 24.8 (1C, t), 16.9 (1C, q). IR (KBr) 1609 cm-1MS (m/e) 260.3 (M+, 22.6), 245.2 (100.0), 203.3 (18.2), 246.2 (17.0).
