p-Toluenesulfonic acid → HCID 67234731, compound

Participants

Reaction Steps

Step-1: In a 500 mL 3-necked flask equipped with a stir-bar and condenser was placed 4-((5-phenylpentyl)oxy)-3-(thiophen-2-yl)benzaldehyde (Intermediate 7) (4.9 g, 1.4 mmol), pinacol (6.6 g, 5.6 mol) and p-toluenesulfonic acid (0.8 g, 4.2 mmol) in benzene (125 mL). The resulting mixture was refluxed for 1 h. TLC analysis (EtOAc: hexane; 1:1) showed the reaction was complete. The reaction was cooled to room temperature, washed with saturated NaHCO3 (2×75 mL), brine (1×75 mL), filtered through 1PS filter paper and concentrated under reduced pressure to give a brown oil. The oil was flash chromatographed over silica gel (100 g) with anhydrous sodium sulfate (20 g) on top packed with hexane. The column was eluted with 12×50 mL of 15% EtOAc in hexane. The product was eluted to give 5.1 g (81%) 4,4,5,5-tetramethyl-2-(4-((5-phenylpentyl)oxy)-3-(thiophen-2-yl)phenyl)-1,3-dioxolane (Intermediate 8) as a yellow oil. HPLC analysis showed a purity of ˜97%. NMR (CDCl3) δ 7.8 (s, 1H), 7.55 (d, 1H), 7.1-7.4 (m, 8H), 6.95 (d, 1H), 6.0 (s, 1H), 4.1 (t, 2H), 2.7 (t, 2H), 1.95 (m, 2H), 1.7 (m, 2H), 1.6 (m, 2H), 1.35 (d, 12H).

Provenance & Evidence