Toluene → 6-(Benzyloxy)-3,4-dihydronaphthalen-2-ylboronic acid

Participants

Reaction Steps

7-Benzyloxy-3-bromo-1,2-dihydro-naphthalene (21.75 g, 0.06900 mol) was azeotroped with toluene (100 mL, 0.9 mol) and dried on the high vacuum for 30 min. This was dissolved in tetrahydrofuran (200 mL, 2 mol), cooled with a dry ice -isopropanol bath under an atmosphere of nitrogen. 1.70 M tert-Butyllithium in pentane (89.3 mL, 0.152 mol) was added slowly, stirred for 10 min. Triisopropyl borate (79.1 mL, 0.345 mol) was added and the mixture was stirred for 1 hour with cooling then brought to r.t. The reaction was quenched with ice-water. The organic layer was separated and the aqueous layer was extracted with EtOAc (3×50 mL). The combined organic layers were washed with water, brine, dried over anhydrous Na2SO4, filtered, concentrated and dried on the high vacuum to give a crude intermediate, 6-(benzyloxy)-3,4-dihydronaphthalen-2-ylboronic acid.

Provenance & Evidence