Triisopropyl borate → (2-(Benzyloxy)-4-chlorophenyl)boronic acid

Temperatur

-70 °C

1-bromo-4-chloro-2-[(phenylmethyl)oxy]benzene (2.976 g, 10 mmol) in dry tetrahydrofuran (40 ml) was cooled to −100° C. n-Butyl lithium, 1.6M solution in hexanes (6.9 ml, 11 mmol) was added dropwise over 10 min under nitrogen. The reaction mixture was then allowed to warm to −70° C. for 1 h. Triisopropylborate (5.514, 30 mmol) was added dropwise under nitrogen. The cooling bath was then removed and the reaction mixture was allowed to warm to room temperature before being quenched with 2N hydrochloric acid (30 mL) and stirred vigorously at room temperature for 1 h. The product was then extracted with ether, dried over magnesium sulphate and evaporated down to an oil which was dissolved in iso-hexane and the solid which separated out was filtered off and dried. Yield 1.89 g.

1. additionwas added dropwise over 10 min under nitrogen
2. customThe cooling bath was then removed
3. temperatureto warm to room temperature
4. custombefore being quenched with 2N hydrochloric acid (30 mL)
5. extractionThe product was then extracted with ether
6. dry with materialdried over magnesium sulphate
7. customevaporated down to an oil which
8. dissolutionwas dissolved in iso-hexane
9. customthe solid which separated out
10. filtrationwas filtered off
11. customdried

ORD-Eintrag

ord-04cd45943b4c460b8383389dd5cdbd51

Quelldatensatz

uspto-grants-2008_11

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07446222B2