4670-29-5

Usage

Also known as

6-hydroxy-5,7,4'-trimethylflavone

Upstream product

• 31273-62-8 7-(1,1-dimethyl-prop-2-ynyloxy)-5-hydroxy-2-methyl-chromen-4-one 
• 35930-31-5 Alloptaeroxylin methyl ether 
• 1111-97-3 3-chloro-3-methylbut-1-yne 
• 1013-69-0 eugenin 
• 13476-24-9 Isoheteropeucenin 
• 126444-80-2 6-Acetyl-5-acetyloxy-7-methoxy-2,2-dimethyl-2H-chroman 
• 126444-81-3 1-(5-Hydroxy-7-methoxy-2,2-dimethyl-chroman-6-yl)-butane-1,3-dione 
• 32550-59-7 6-Acetyl-5-hydroxy-7-methoxy-3,4-dihydro-2,2-dimethyl-2H<1>benzopyran 
• 54303-77-4 5-methoxy-2,8,8-trimethyl-9,10-dihydro-4H,8H-benzo<1,2-b:5,6-b'>dipyran-4-one 
• 24128-11-8 6-Acetyl-5,7-dihydroxy-3,4-dihydro-2,2-dimethyl-2H-<1>benzopyran 

Downstream Products

• 35930-31-5 Alloptaeroxylin methyl ether 
• 29507-75-3 spatheliachromen 
• 27305-38-0 alloptaeroxylin acetate 
• 34411-93-3 spatheliabischromene 

Relevant academic research and scientific papers

Synthesis of methylisospatheliachromene, alloptaeroxylin and alloptaeroxylin methyl ether

6-Acetyl-7-acetyloxy-(II)-, 8-acetyl-7-acetyloxy-5-methoxy-(VII)- and 6-acetyl-5-acetyloxy-7-methoxy-(XII)-2,2-dimethyl-2H-chromans, derived from the corresponding acetylhydroxychromans(I), (VI) and (XI), on Baker-Venkataraman rearrangement with KOH-pyridine yield the β-diketones (III), (VIII) and (XIII) respectively.These on acid-catalysed cyclisation followed by dehydrogenation, afford the corresponding 2,2-dimethyl-2H-pyranochromones (V), (X) and (XV).Alloptaeroxylin methyl ether (XV) on demethylation with (AlCl3-CH3CN) yields alloptaeroxylin (XVI).

A Study of the Base-catalysed Wessely-Moser Rearrangement of Angularly Condensed 2,2-Dimethyl-2H-pyrano Derivatives of 5-Hydroxy-2-methylchromones and 2,3-Diphenylchromones and related 1-Hydroxyxanthone

2-Methyl group in 5-hydroxy-2,8,8-trimethyl-8H-pyranochromone (4a) does not hinder base-catalysed isomerisation to afford the corresponding linear isomer (5a); whereas the presence of of phenyl group in position 2 and 3 as in 4c brings no such change.Similarly, 6-hydroxy-3,3-dimethyl-3H-pyranoxanthone (8) does not undergo alkali isomerisation. 5,7-Dihydroxy-2-methylchromone (2a) with 2-chloro-2-methyl-3-butyne in the presence of K2CO3, KI and DMF yields both the linear and angular 2,2-dimethyl-2H-pyrano derivatives (5a and 4a respectively) besides the 1,1-dimethylpropargyl ether (3a), the ratio being 2:4:3.However, under similar conditions 5,7-dihydroxy-2,3-diphenylchromone (2b) yields 3b, 4c and 5c in the ratio of only 5:14:1; again the tendency of forming linear isomer (5c) is far less than that of the angular isomer (4c).

A New Synthesis of Alloptaeroxylin, Its Methyl Ether and Related Compounds

Claisen condensation of 6-acetyl-5,7-dihydroxy-2,2-dimethylchroman (I) with sodium and ethyl acetate gives isoheteropeucenin (II) and isopeucenin (III).Benzylic bromination of II and III with NBS followed by dehydrobromination with pyridine affords alloptaeroxylin (IV) and dehydroisopeucenin (V) respectively.IV on methylation gives alloptaeroxylin methyl ether (VI).VI has also been synthesized by an alternate route.