68634-30-0

Upstream product

• 4655-89-4 8-Acetyl-7-hydroxy-5-methoxy-3,4-dihydro-2,2-dimethyl-2H-<1>benzopyran 
• 94-30-4 ethyl 4-methoxybenzoate 
• 86978-02-1 1-(7-Hydroxy-5-methoxy-2,2-dimethyl-chroman-8-yl)-3-(4-methoxy-phenyl)-propane-1,3-dione 
• 86978-01-0 4-Methoxy-benzoic acid 8-acetyl-5-methoxy-2,2-dimethyl-chroman-7-yl ester 

Downstream Products

• 86978-02-1 1-(7-Hydroxy-5-methoxy-2,2-dimethyl-chroman-8-yl)-3-(4-methoxy-phenyl)-propane-1,3-dione 
• 143725-44-4 5-Methoxy-8-(4-methoxy-phenyl)-2,2-dimethyl-2H-pyrano[2,3-f]chromen-10-one 

Relevant academic research and scientific papers

A Facile Synthesis of Isopongaflavone, Atalantoflavone Dimethylether, Racemoflavone Dimethylether and their Analogues

A convenient route to pyranoflavones (natural and synthetic) from acetyl hydroxy chroman via the corresponding analogues by the use of Claisen condensation in the key step is reported.Keywords: 2-Aryl-8,8-dimethyl-6,7-dihydro-4H,8H-benzodipy

Baker-Venkataraman Rearrangement of o-Aroyloxyacetyldihydrobenzopyrans - Synthesis of 3,4-Dihydro-2,2-dimethyl-2H-pyranoflavones

Reactions of 6-acetyl-7-hydroxy-3,4-dihydro-2,2-dimethyl-2H-benzopyran (I) and 8-acetyl-7-hydroxy-5-methoxy-3,4-dihydro-2,2-dimethyl-2H-benzopyran (II) with 4-methoxybenzoyl chloride and 3,4-methylenedioxybenzoyl chloride give the respective o-aroyloxyacetyldihydrobenzopyrans (III, VI, IX and XII).These on Baker-Venkataraman rearrangement in the presence of pyridine and KOH afford the diaroylmethanes (IV, VII, X and XIII), which undergo cyclisation in the presence of glacial acetic acid and fused sodium acetate to the corresponding dihydropyranoflavones (V, VIII, XI and XIV).