Acetonitrile → (3-Cyclopentyloxy-4-methoxy-phenyl)-phenyl-methanone

Participants

Reaction Steps

To an ice bath cooled stirred solution of N-methoxy-N-methyl-3-cyclopentoxy-4-methoxybenzamide (1.2 g, 4.3 mmol) in 15 mL of anhydrous ether was added a 3 M solution of phenylmagnesium bromide (3.6 mL, 10.8 mmol) in ether dropwise over a 20 minute period. A white gum precipitated from the mixture and dry THF (6 mL) was added to facilitate stirring. The reaction mixture was allowed to warm to room temperature and was stirred for 4 hours. The reaction was then quenched at 0° C. with a saturated aqueous solution of ammonium chloride (8 mL). The resulting mixture was allowed to warm to room temperature and was diluted with ethyl acetate (10 mL). The organic layer was separated and sequentially washed with 1 N citric acid (2×10 mL), saturated NaHCO3(aq) (2×10 mL), and brine (2×10 mL). The organic layer was then dried over MgSO4, filtered and concentrated in vacuo to give a viscous oil. The crude product was purified by flash column chromatography (silica gel, methylene chloride) and the resulting product was then dried in vacuo (40° C., <1 mmHg) to afford 0.75 g (60%) of a slightly impure product as a white solid: mp 73.5-75.0° C.; 1H NMR (CDCl3) δ 7.80-7.72 (m, 2H), 7.63-7.15 (m, 5H), 6.94-6.79 (m, 1H), 4.91-4.78 (m, 1H), 3.92 (s, 3H), 2.09-1.50 (m, 8H) also some impurity in the aromatic region; 13C NMR (CDCl3) δ 195.7, 153.9, 147.5, 138.3, 131.8, 129.7, 128.1, 125.1, 120.3, 115.5, 110.3, 80.5, 56.1, 32.7, 24.1; HPLC (Waters Nova-Pak/C18 column, 3.9×150mrn, 4 micron, 1 mL/min, 60/40, CH3CN/0.1% H3PO4(aq)) 6.2, min 99%.

Provenance & Evidence