Phosphorus oxide (P4O10) → 2,2-Difluoropropanoic anhydride
Reaction equation
[F:1][C:2]([F:7])([CH3:6])[C:3]([OH:5])=[O:4].O=P12OP3(OP(OP(O3)(O1)=O)(=O)O2)=O>C(Cl)Cl>[F:1][C:2]([F:7])([CH3:6])[C:3]([O:5][C:3](=[O:4])[C:2]([F:7])([F:1])[CH3:6])=[O:4]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
Synthesis: Step 1: To a solution of 2,2-difluoropropanoic acid (330 mg, 2.97 mmol) in DCM (5 mL) was added P2O5 (3.3 g, 29.7 mmol) at room temperature and the mixture was stirred for 2 days to give 2,2-difluoropropanoic anhydride. To a suspension of Intermediate A-2a (170 mg, 0.59 mmol) in TEA (5 mL) was added dropwise the 2,2-difluoropropanoic anhydride in DCM at 0˜10° C. The mixture was stirred at room temperature for 2 h. The volatiles were evaporated and the residue was purified by prep-TLC (PE:EA=1:1) to afford methyl 4-(2-(1,1-difluoroethyl)-7-hydroxy-4-oxo-4H-chromen-3-yl)benzoate as brown oil (45 mg, 21%).
Workup
- customSynthesis
Sources & evidence
- ORD record
- ord-4ab0964d892c4889b2de676a43ac2fd6
- Source dataset
- uspto-grants-2013_07
- Patent number
- US08481590B2
Reaction notes
Loading…