3-Bromoquinoline → Quinoline-3-boronic acid

Temperature

-40 °C

To a solution of 3-bromoquinoline (Sigma-Aldrich, St. Louis, USA) (1 eq, 14.0 mmol, 1.94 ml) in toluene/THF (4:1, 25 ml), triisopropylborate (1.2 eq, 16.8 mmol, 3.94 ml) is added. The mixture is cooled to −40° C., then n-butyl lithium (1.6 M in THF, 1.2 eq, 17 mmol, 10.5 ml) is added within 30 min. After stirring for additional 30 min at this temperature, the cooling bath is removed and the reaction mixture is allowed to to warm up to −20° C. before quenching with aqueous HCl solution (2 N). The mixture is adjusted to pH 7 by using aqueous NaOH solution (4 N), then it is saturated with NaCl, and extracted with THF. The organic layer is concentrated in vacuo, and the resulting solid is recrystallized in MeCN yielding the title compound, [M+H]+=173.

1. customthe cooling bath is removed
2. temperatureto to warm up to −20° C.
3. custombefore quenching with aqueous HCl solution (2 N)
4. extractionextracted with THF
5. concentrationThe organic layer is concentrated in vacuo
6. customthe resulting solid is recrystallized in MeCN yielding the title compound, [M+H]+=173

ORD record

ord-956094d9005947bf9f14d4c7f073a0ef

Source dataset

uspto-grants-2012_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08314112B2