5-bromofuran-2-carbaldehyde

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 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. 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) concentrated to dryness under reduced pressure

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of 5-bromo-2-furaldehyde (1.76 g) and morpholine (1.00 ml) in 40 mL anhydrous THF at room temperature was added acetic acid (0.60 mL) followed by sodium triacetoxyborohydride (3.28 g). The mixture was stirred at room temperature for 3 h and then poured into a saturated solution of sodium bicarbonate (100 mL). After stirring vigorously for 5 min the layers were separated and the aqueous layer was extracted with EtOAc. The combined organic layers were washed with brine, dried (Na2SO4), filtered and evaporated to dryness. Purification of the residue by flash chromatography afforded 2.09 g (8.49 mmol, 84% yield) of 4-(5-bromo-2-furylmethyl)morpholine. After stirring vigorously for 5 min the layers were separated the aqueous layer was extracted with EtOAc The combined organic layers were washed with brine dried (Na2SO4) filtered evaporated to dryness Purification of the residue by flash chromatography