Dichloromethane → Methyl 4-isopropyl-2-methylbenzoate

Participants

Reaction Conditions

Reaction Steps

A dried round bottom flask with stir bar was purged with nitrogen and charged with diisopropyl zinc (25 mL of a 1 M solution in THF, 25 mmol, 2.0 equiv). Methyl 4-bromo-2-methylbenzoate (compound 152.1, 2.86 g, 12.5 mmol, 1.0 equiv) in 1,4-dioxane (25 mL) was added followed by addition of Pd(dppf)2Cl2.DCM (1.02 g, 1.25 mmol, 0.1 equiv) (exothermic upon catalyst addition). The system was purged with additional nitrogen then argon and heated to 100° C. for 4 hours then stirred at room temperature for 12 hours. The mixture was carefully quenched with 1M HCl (ag., 12 mL) (some bubbling) and then diluted with water (100 mL) and ethyl acetate (150 mL) and mixed. The mixture was filtered through celite and washed with water and ethyl acetate (2×25 mL each). The layers were separated and the aqueous was extracted with addition ethyl acetate (50 mL). The combined organics were washed with brine (50 mL), dried (Na2SO4), and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography (hexanes to 6% ethyl acetate) to obtain the title compound as a colorless oil (2.31 g, 96%). 1H NMR (400 MHz, CDCl3): δ 7.86 (d with fine str, J=8.8 Hz, 1H), 7.12-7.07 (m, 2H), 3.87 (s, 3H), 2.90 (septet, J=6.8 Hz, 1H), 2.59 (s, 3H), 1.25 (d, J=6.8 Hz, 6H).

Provenance & Evidence