Synthesis
2,4,6-TRIPHENYLPYRYLIUM TETRAFLUOROBORATE can be prepared from acetophenone and benzaldehyde via a one-step reaction.
Under nitrogen protection, a mixture of acetophenone (24.0 g, 0.2 mol), benzaldehyde (10.6 g, 0.1 mol), and BF3·Et2O (3.0 mL) was heated to 100 °C and reacted for 2 h. After cooling to room temperature, an appropriate amount of diethyl ether was added, the precipitate was filtered, washed with diethyl ether, and dried to give yellow crystals, with a yield of 65%.
Description
2,4,6-Triphenylpyrylium Tetrafluoroborate converts primary amines into pyridinium salts which on reaction with nucleophiles NuH afford R-Nu.
Chemical Properties
Yellow crystalline powder
Uses
2,4,6-Triphenylpyrylium tetrafluoroborate was used as a sensitizer to carry out the photooxidation of cathecol. It was also used in the preparation of three
N-alkylpyridinium photosensitizers by reacting with (1
R,2
S)-(-)-norephedrine, (
S)-(+)-2-(aminomethyl)pyrrolidine and (
R)-(-)-1-cyclohexylethylamine.
reaction suitability
reaction type: Photocatalysis
reagent type: catalyst
storage
may be stored indefinitely. Reports on possible mutagenic activity make it desirable to avoid direct contact with skin.
