4-Formylbenzoic acid → 4-Formylbenzoyl chloride
Reaction equation
[Cl-].[Cl:2]C=[N+](C)C.[C:7]([C:10]1[CH:17]=[CH:16][C:13]([CH:14]=[O:15])=[CH:12][CH:11]=1)(O)=[O:8]>C(Cl)Cl>[CH:14]([C:13]1[CH:16]=[CH:17][C:10]([C:7]([Cl:2])=[O:8])=[CH:11][CH:12]=1)=[O:15]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 0 °C
Procedure
A suspension of (chloromethylene)dimethylammonium chloride (Vilsmeier Reagent; 37.7 g, 0.280 mol) in CH2Cl2 (300 mL) at 0° C. was treated with 4-carboxybenzaldehyde (40.0 g, 267 mmol) in one portion. The reaction mixture was stirred at 0° C. for 30 min, then at room temperature for 2 h. HPLC analysis of an aliquot of the reaction mixture quenched into MeOH indicated consumption of 4-carboxybenzaldehyde. The reaction mixture was filtered through a medium porosity glass frit. The filtrate, containing the title compound, was stored at 0° C., and used in the next step without further manipulation.