Reaction #2075720

Reaction equation

n-butyllithium

1-chloro-2,3-difluorobenzene

2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane

→

title compound

2-(4-Chloro-2,3-difluorophenyl)-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane

Solvents

THF

—

hexanes

water

ethyl acetate

Conditions

Workup

1. 1
   Temperatureto warm to ambient temperature
2. 2
   Extractionand the organic phase was extracted twice with water
3. 3
   ExtractionThe product was then extracted with ethyl acetate
4. 4
   OtherThe organic phase was dried
5. 5
   Concentrationconcentrated under vacuum

Procedure

A 2.5 M solution of n-butyllithium (2.69 ml, 6.73 mmol) in hexanes was added dropwise to a solution of 1-chloro-2,3-difluorobenzene (1 g, 6.73 mmol) in THF (25 mL) cooled to −78° C. After 45 min at −78° C., 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1.253 g, 6.73 mmol) was added dropwise after which the reaction mixture was allowed to warm to ambient temperature. The reaction mixture was diluted with water and ethyl acetate; and the organic phase was extracted twice with water. The aqueous extracts were combined and acidified with 12N HCl to pH 3. The product was then extracted with ethyl acetate. The organic phase was dried and concentrated under vacuum to yield the title compound as an oil product (0.93 g, 50% yield): 1H NMR (CDCl3): δ 7.42 (m, 1H), 7.17 (m, 1H), 1.37 (s, 12H).

Source