57646-01-2

Upstream product

• 853925-93-6 3,6-dimethyl-4-oxo-4H-chromene-2-carboxylic acid 
• 938-45-4 2-propionyl-p-cresol 
• 109-94-4 formic acid ethyl ester 
• 57646-07-8 3,6-dimethylchroman-4-one 
• 139449-24-4 3-Benzenesulfonyl-3,6-dimethyl-chroman-4-one 
• 67064-52-2 3-bromo-6-methyl-chroman-4-one 
• 139449-20-0 6-Methyl-3-phenylsulfanyl-chroman-4-one 
• 139449-22-2 3-Benzenesulfonyl-6-methyl-chroman-4-one 
• 106-44-5 p-cresol 
• 64207-03-0 1-(2-hydroxy-5-methylphenyl)-2-methylpropan-1-one 

Downstream Products

• 938-45-4 2-propionyl-p-cresol 

Relevant academic research and scientific papers

C-H Functionalization via Remote Hydride Elimination: Palladium Catalyzed Dehydrogenation of ortho-Acyl Phenols to Flavonoids

Although deprotonation of electron-poor C-H bonds to carbon anions with bases has long been known and widely used in organic synthesis, the hydride elimination from electron-rich C-H bonds to carbon cations or partial carbocations for the introduction of nucleophiles is a comparatively less explored area. Here we report that the carbonyl β-C(sp3)-H bond hydrogens of ortho-acyl phenols could be substituted by intramolecular phenolic hydroxyls to form O-heterocycles, followed by dehydrogenation of the O-heterocycle into flavonoids. The cascade reaction is catalyzed by Pd/C without added oxidants and sacrificing hydrogen acceptors.

A Facile Synthesis of 3-Alkylchromanones and Chromones

A simple and high yielding route to 3-alkylchromanones and 3-alkylchromones has been achieved from 3-alkyl-3-phenylsulphonyl-4-chromanones.

Oxidation of 4-Chromanones with Thalium(III) Nitrate

Treatment of 4-chromanones 1a-g with thalium(III) nitrate in acidic methanol results mainly in dehydrogenation, whereas α-methoxylation and/or Taylor-McKillop rearrangement predominante in trimethyl orthoformate.The mechanistic features of these oxidations are briefly discussed.