Trimethyl borate → 3-(3-Heptyl-1-methylureido)phenylboronic acid

Beteiligte Stoffe

Reaktionsschritte

In a manner similar to that of Example (18a), by reaction of 113 g (0.345 mol, 1 eq) of 1-(3-bromophenyl)-3-heptyl-1-methylurea in 1.13 L of tetrahydrofuran, 127 mL (0.38 mol, 1.1 eq) of methyllithium, 530 mL (0.76 mol, 2.2 eq) of a 1.7M solution of tert-butyllithium in pentane and 97 mL (0.904 mol, 2.2 eq) of trimethyl borate, and after purification by chromatography on silica gel (50/50 heptane/ethyl acetate) and crystallization from ethyl acetate/heptane, 36.0 g of 3-(3-heptyl-1-methylureido)phenylboronic acid are obtained in the form of a pinkish powder. Yield=36%

Herkunft & Nachweise