Trifluoroacetic acid → 1,1,5-Trimethylindan

Participants

Reaction Steps

A solution of 3,3,6-trimethylindan-1-one (2.62 g, 15 mmol) in trifluoroacetic acid (12 mL, 150 mmol) was stirred at room temperature under nitrogen as triethylsilane (5.3 mL, 33 mmol) was added dropwise. The solution was stirred overnight. The reaction mixture was treated with saturated sodium bicarbonate, followed by extraction with ether. The combined ether layers were dried over anhydrous sodium sulfate and concentrated. MS analysis of the crude material showed the presence of triethylsilanol and hexaethyldisiloxane as the major by-products. The crude material was subjected to fractional distillation to afford 1,1,5-trimethylindane (307) (2.19 g, 92%) as a colorless liquid. Boiling pt 86-88° C. at 0.8 mmHg; 1H NMR (CDCl3) δ 1.24 (s, 6H), 1.90 (t, 2H), 2.31 (s, 3H), 2.85 (t, 2H), 7.02 (m, 3H).

Provenance & Evidence