62756-35-8

Upstream product

• 5751-48-4 2-methylchromone 
• 109737-57-7 6-methyl-2-phenyl-1,3,6,2-dioxazaborocane-4,8-dione 
• 24388-23-6 2-phenyl-4,4,5,5-tetramethyl-1,3,2-dioxoborole 
• 98-80-6 phenylboronic acid 
• 90-02-8 salicylaldehyde 
• 5631-75-4 2,3-dihydro-2-methyl-4H-1-benzopyran-4-one 
• 127-66-2 2-Phenyl-3-butyn-2-ol 
• 98-86-2 acetophenone 
• 157462-03-8 4-acetoxy-2-methyl-2-phenylbenzopyran 
• 118-93-4 o-hydroxyacetophenone 

Downstream Products

• 157462-03-8 4-acetoxy-2-methyl-2-phenylbenzopyran 
• 157462-05-0 2-methyl-2-phenyl-2,3-dihydrobenzopyran-3,4-dione 
• 1071635-00-1 Z-3-hydroxy-2-methyl-2-phenyl-2,3-dihydrobenzopyran-4-one 
• 155914-03-7 3-chloro-3-chlorosulfenyl-2-methyl-2-phenylchroman-4-one 
• 154324-91-1 4-bromo-2-methyl-2-phenyl-2H-chromene 

Relevant academic research and scientific papers

Synthesis of Flavanones via Palladium(II)-Catalyzed One-Pot β-Arylation of Chromanones with Arylboronic Acids

A total of 47 flavanones were expediently synthesized via one-pot β-arylation of chromanones, a class of simple ketones possessing chemically unactivated β sites, with arylboronic acids via tandem palladium(II) catalysis. This reaction provides a novel route to various flavanones, including natural products such as naringenin trimethyl ether, in yields up to 92percent.

Palladium-catalyzed conjugate addition of arylboronic acids to 2-substituted chromones in aqueous media

Palladium-catalyzed conjugate additions of arylboronic acids to 2-alkylchromones are reported. The conjugate additions occur in aqueous media in the presence of a catalyst generated from palladium trifluoroacetate and 1,10-phenanthroline, and the flavanone derivatives containing a fully-substituted carbon center are formed in up to 90% yield.

Convenient and highly efficient routes to 2 H-chromene and 4-chromanone derivatives: Iodine-promoted and p-toluenesulfonic acid catalyzed cascade cyclizations of propynols

A convenient strategy is presented for the easy preparation of a series of 2 H-chromenes under mild conditions through iodocyclization of readily accessible propynols. In addition, various 4-chromanones can be synthesized through a p-toluenesulfonic acid catalyzed cascade cyclization with high efficiency (yields up to 99%). Our developed reaction systems are proven to have good functional-group applicability and can be scaled up to gram quantities in satisfactory yields. These systems also provide a new synthetic strategy for two types of important flavonoid skeleton without using costly and toxic metal catalysts. Additionally, the resulting halides could be further exploited in subsequent palladium-catalyzed coupling reactions, so these compounds could act as potential intermediates for the construction of some valuable drug molecules.

Photolysis of 3-bromochroman-4-ones

Photolysis of 3-bromochroman-4-ones (1a-f) leads to debrominated chromanones (2a-f) and chromones (3a-f) as major products. Their formation is accounted for in terms of primary cleavage of the carbon halogen bond to give α-carbonyl radicals (I) and/or cations (II). In the case of the 2,2-disubstituted compounds (1d-f), intermediates (II) undergo rearrangement with 1,2-shift of the phenyl or benzyl substituent prior to deprotonation. Minor by-products are the pentacyclic pyrone (4e) or 2-methylchromone (3a) (starting from 1e and 1f, respectively).

Electron Transfer Oxidation of Enol Derivatives of 2,3-Dihydrobenzopyran-4-ones

Dihydrobenzopyrones 1a-c and their enol acetates 3a-c have been submitted to oxidation under single electron transfer (SET) conditions, using three alternative ways of activation: chemical oxidation with cerium(IV) ammonium nitrate (CAN), photochemical oxidation using triphenylpyrylium tetrafluoroborate (TPT) as sensitizer or electrochemical oxidation.The most significant products obtained are diketones 4, hydroxyketones 5, rearranged benzopyrones 6, enones 9 and, in the case of enol acetate 3c, 2-methylchromone (10) and 1,2-diphenylethane (13).These results are rationalized according to three major pathways from the radical cations: i) formation of the α-carbonyl radicals I (trough deprotonation of the enols 2(+). or cleavage of the carbonyl-oxygen bond of their acetates 3(+).), eventually followed by secondary oxidation to the carbenium ions II, ii) breaking of the bond linking C2 with one of the substituents and iii) ring opening.

A New Reaction of α-Chloro-α-chlorosulfenyl Ketones: Facile Syntheses of 3,3-Dichloro- and 3-Chloro-Chroman-4-ones and Thiochroman-4-ones

3-Chloro-3-chlorosulfenylchroman-4-ones are efficiently obtained from chroman-4-ones by treatment with thionyl chloride.Direct oxidation affords 3,3-dichlorochroman-4-ones, whilst conversion to the sulfenamides prior to oxidation provides a facile route to 3-chlorochroman-4-ones.