2-(4-(Bromomethyl)phenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane → 1-{2-Biphenyl-4-yl-1-phenyl-1-[4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-benzyl]-ethyl)-1H-benzotriazole

Participants

Reaction Conditions

Reaction Steps

A solution of 4.26-A of Step 1 (450 mg, 1.2 mmol) in tetrahydrofuran (14 mL) was cooled to −78° C. and treated with n-butyllithium (0.62 mL, 2.5 M in hexanes) dropwise. The reaction mixture was stirred at −78° C. for 10 min and 2-[4-(bromomethyl)phenyl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (410 mg, 1.4 mmol) in tetrahydrofuran (2 mL) was added dropwise. The reaction mixture was stirred at −78° C. for 1 h, quenched with sat. ammonium chloride (2 mL), and extracted with ethyl acetate (15 mL). The organic layer was separated and washed with brine (5 mL), dried with sodium sulfate, filtered, and concentrated to a crude residue which was purified by flash column chromatography to yield the desired product (350 mg, 50%). LCMS found for C39H38BN3O2Na (M+Na)+: m/z=614.

Provenance & Evidence