Hydrochloric Acid → HCID 68502575, compound

Participants

Reaction Conditions

Reaction Steps

A stirred suspension of Zn dust (2.45 g, 37.5 mmol), 3,3,5,5-tetramethylcyclohexanone (1.93 g, 12.5 mmol), 19 (3.00 g, 12.5 mmol) and THF (100 mL) under N2 was cooled to −10° C. and a 1 M solution of TiCl4 in toluene (19.5 mL) was added, dropwise, over 10 min. After addition was complete the reaction was allowed to warm to room temperature and then heated at 90° C. for 7 h. The reaction was cooled to room temp and then chilled to −10° C. and concentrated HCl (15 mL) added dropwise followed by water (15 mL). The dark reaction turns a pale purple. EtOAc (60 mL) was added and the mixture washed with water (2×60 mL) and brine (1×60 mL) then dried (MgSO4) and concentrated to 5.1 g of a pale yellow oil. The crude product was purified by column chromatography on 200 g silica gel with a 100% hexanes to 2% EtOAc/hexanes gradient to afford 2.84 g of a white solid which was recrystallized from hexanes. Yield: 0.95 g (21%) of the title compound 20 which was contaminated with ˜5% of the pinacol intermediate. 1H NMR (400 MHz, DMSO-d6): δ 7.87 (d, J=8.2 Hz, 2H), 7.15-7.31 (m, 7H), 3.80 (s, 3H), 1.89 (s, 2H), 1.86 (s, 2H), 1.25 (s, 2H), 0.87 (s, 6H), 0.86 (s, 6H). Anal. Calcd for C25H30O2: C, 82.80; H, 8.36. Found: C, 82.94; H, 8.51.

Provenance & Evidence