2-Phenylpropionic acid → 2,5,5-trimethyl-2-phenylhexanoic Acid

Participants

Reaction Steps

Lithium bis(trimethylsilyl)amide (32.3 g, 193 mmol) was added to 80 mL of tetrahydrofuran and the resulting solution was cooled in an ice bath. Addition of a solution of 2-phenyl-propionic acid (11.6 g, 77.3 mmol) in 10 mL of tetrahydrofuran to the reaction solution was followed by addition of 1-bromo-3,3-dimethyl-butane (20.4 g, 124 mmol). The reaction vessel was removed from the cooling bath, placed in a 50° C. oil bath, and the reaction solution was stirred for 17 hours. After concentration, the resulting residue was dissolved in 250 mL of 1 N NaOH, washed with 250 mL of 2:1 hexane/iso-propyl acetate, acidified to pH 1 with 6 N HCl, and extracted with ethyl acetate (3×300 mL). The combined organic layers were dried over Na2SO4 and concentrated to give 17.3 g (96%) of clear oil. 1H NMR (300 MHz, CDCl3): δ ppm 0.86 (s, 9H) 1.09 (m, 2H) 1.56 (s, 3H) 1.99 (m, 2H) 7.33 (m, 5H).

Provenance & Evidence