8-Bromo-2H-1-benzopyran-2-one

To a solution of 3-bromo-2-hydroxybenzaldehyde (402 mg, 2.0 mmol) in NMP (5 ml.) was added carbethoxymethylene triphenylphosphorane (765 mg, 2.2 mmol). The reaction was heated at 210 To a solution of 3-bromo-2-hydroxybenzaldehyde (402 mg, 2.0 mmol) in NMP (5 ml.) was added carbethoxymethylene triphenylphosphorane (765 mg, 2.2 mmol). The reaction was heated at 210 (3) Weigh 1.8g of Br-C8 (8.89mmol), 0.28 g of Pd(PPh3)4 (0.24 mmol) in a SCHLENK reaction tube under N2 atmosphere, 35 mL of toluene was added, and 3.53 g of tri-n-butyl 2-pyridinium (9.60 mmol) was added dropwise.The reaction was stirred at 110 C for 16 h. After completion of the reaction, the mixture was cooled to room temperature, and the solvent was evaporated under reduced pressure.It was separated and purified by silica gel column chromatography, and the mobile phase was dichloromethane.Finally, L-C8 was obtained as a white solid 1.49 g, and the yield was 83.2%.General procedure: General synthetic procedure for 3a/3b/3c: 6-Bromocoumarin(0.5 g, 2.23 mmol), (4-ethynyl)benzaldehyde (0.29 g, 2.23 mmol)were dissolved in THF-triethylamine (1:1, v/v, 120 mL) and themixture was deaerated for 10 min with nitrogen bubbling and thenPd(PPh3)2Cl2 (31 mg, 2mol%), PPh3 (23 mg, 4 mol%)and CuI (8 mg, 2mol%) were added. The solution was deaerated for an additional5 min; after that, reaction was left under nitrogen at 60C for 12 h.After completion of the reaction, the reaction mixture was cooledat room temperature and the solvent was evaporated. The crudeproduct was dissolved in CH2Cl2 and purified by a columnchromatography on a silica gel using (chloroform) as an eluent.

Molecular Weight:225.04
XLogP3:2.6
Hydrogen Bond Acceptor Count:2
Exact Mass:223.94729
Monoisotopic Mass:223.94729
Topological Polar Surface Area:26.3
Heavy Atom Count:12
Complexity:225
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes