Reaktion #2017677

Reaktionsgleichung

1,4-phenylenebisboronic acid

5-bromofuran-2-carboxaldehyde

Na2CO3

→

11

Ausbeute 93.0%

5-[4-(5-Formylfuran-2-yl)-phenyl]-furan-2-carboxaldehyde

Ausbeute 93.0%

Lösungsmittel

methanol

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe solvent was evaporated
2. 2
   Sonstigethe precipitate was partitioned between methylene chloride (300 mL) and 2 M aqueous Na2CO3 (15 mL)
3. 3
   workup.ADDITIONcontaining 5 mL of concentrated ammonia
4. 4
   TrocknenThe organic layer was dried (Na2SO4)
5. 5
   Einengenconcentrated to dryness under reduced pressure

Vorschrift

To a stirred solution of 5-bromofuran-2-carboxaldehyde (10 mmol), and tetrakis(triphenylphosphine) palladium (400 mg) in toluene (20 ml.) under a nitrogen atmosphere was added 10 mL of a 2 M aqueous solution of Na2CO3 followed by 1,4-phenylenebisboronic acid (5 mmol) in 6 mL of methanol. The vigorously stirred mixture was warmed to 80° C. for 12 h. The solvent was evaporated, the precipitate was partitioned between methylene chloride (300 mL) and 2 M aqueous Na2CO3 (15 mL) containing 5 mL of concentrated ammonia. The organic layer was dried (Na2SO4), and then concentrated to dryness under reduced pressure to afford 11 in 93% yield; mp 233-234° C. (EtOH). 1H NMR (DMSO-d6); δ 9.64 (s, 2H), 8.01 (s, 4H), 7.70 (d, J=3.6 Hz, 2H), 7.43 (d, J=3.6 Hz, 2H). MS (ESI) m/e (rel. int.): 266 (M+, 100), 238 (5), 209 (25). Anal. Calc. for C16H10O4: C %, 72.16; H %, 3.78. Found C %, 72.41; H %, 3.93.

Quelle