Reaktion #643624

Reaktionsgleichung

methanol

2-fluoro-5-trifluoromethylphenylisocyanate

triethylamine

4-(4,4,5,5-tetramethyl[1,3,2]dioxaborolan-2-yl)aniline

→

1-(2-fluoro-5-trifluoromethylphenyl)-3-[4-(4,4,5,5-tetramethyl[1,3,2]dioxaborolan-2-yl)phenyl]urea

Ausbeute 74.9%

Lösungsmittel

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigefinally, evaporated to dryness under reduced pressure
2. 2
   SonstigeThe residue thus obtained
3. 3
   Sonstigeis purified by chromatography on silica using, as eluent
4. 4
   workup.ADDITIONThe fractions containing the expected product
5. 5
   Einengenare concentrated to dryness so as

Vorschrift

936 mg of 2-fluoro-5-trifluoromethylphenylisocyanate and then 0.64 ml of triethylamine are added to a solution of 1 g of 4-(4,4,5,5-tetramethyl[1,3,2]dioxaborolan-2-yl)aniline in 15 ml of tetrahydrofuran, at ambient temperature. The reaction medium is stirred at ambient temperature for 18 h, and then treated with methanol and then, finally, evaporated to dryness under reduced pressure. The residue thus obtained is purified by chromatography on silica using, as eluent, a (99.5/0.5 then 90/10) methylene chloride/methanol mixture. The fractions containing the expected product are concentrated to dryness so as to give 1.45 g of 1-(2-fluoro-5-trifluoromethylphenyl)-3-[4-(4,4,5,5-tetramethyl[1,3,2]dioxaborolan-2-yl)phenyl]urea in the form of a white solid. MS (ES) MH+ m/z=425.

Quelle