1-Propylboronic acid catechol ester → Benzyl 6-[(tert-butoxycarbonyl)amino]-2-methyl-3-propylbenzoate

Participants

Reaction Conditions

Reaction Steps

A mixture of Example 126A (0.52 g, 1.25 mmol), 2-propyl-1,3,2-benzodioxaborole (0.50 g, 3.0 mmol), Pd(dppf)Cl2 (24 mg, 0.03 mmol) and Tl2CO3 (0.75 g, 1.6 mmol) in THF (15 mL) in a scintillation vial was purged with argon, sealed, and shaken at 90° C. for 72 hours. The mixture was treated with brine (25 mL) and extracted with ethyl acetate. The extract was dried (Mg2SO4), filtered, and concentrated. The residue was purified by flash column chromatography on silica gel eluting with 5% ethyl acetate/hexanes to provide the desired product (0.38 g, 80.0%). 1H NMR (CDCl3) δ 0.94 (t, 3H), 1.48 (s, 9H), 1.55 (m, 2H), 2.24 (s, 3H), 2.54 (t, 2H), 5.38 (s, 2H), 7.15 (d, 1H), 7.36-7.46 (m, 5H), 7.77 (d, 1H).

Provenance & Evidence