119755-19-0

Upstream product

• 4919-77-1 3-benzoyl-2-methyl-4H-chromen-4-one 
• 4637-24-5 N,N-dimethyl-formamide dimethyl acetal 
• 93-89-0 benzoic acid ethyl ester 
• 118-93-4 o-hydroxyacetophenone 
• 1469-94-9 1-(2-hydroxyphenyl)-3-phenyl-1,3-propanedione 

Downstream Products

• 119755-13-4 10-Phenyl-8H-5-oxa-8-aza-cyclohepta[b]naphthalen-11-one 
• 119755-11-2 2-Oxy-1-phenyl-10-oxa-2-aza-anthracen-9-one 
• 119755-21-4 1-Phenyl-10-oxa-2-aza-anthracen-9-one 
• 119755-16-7 C₂₀H₁₄N₂O₃ 
• 119755-42-9 2-Phenyl-3-(2-phenyl-2H-pyrazol-3-yl)-chromen-4-one 

Relevant academic research and scientific papers

Benzopyrans. Part 41.1 Reactions of 2-(2-dimethylaminovinyl)-lbenzopyran-4-ones with various dienophiles

Dienamine 1 with W-phenylmaleimide and chromenone 14 as well as 15 produces, through initial [4 + 2]cycloaddition, xanthenones 10 and 18, respectively. Initial Michael addition of 1 to chromenones 14 and 16, and dimethyl acetylenedicarboxylate (DMAD), triggers the formation of xanthenone 19, 4-azaxanthenone 26 and substituted fumarate 49, respectively. Initial [2 + 2]cycloadducts of dienamines 1-3 with electrophilic acetylenes always undergo further transformations. Thus, 1 with DMAD, dibenzoylacetylene and ethyl propiolate (EP) ultimately gives xanthenones 33, 34 and 37, respectively, the latter being admixed with flavone 43. Enamine 2, cyclisable to xanthenone 11, gives 33 and 35 with DMAD, and 37 and 44 with EP. Reaction of 3 with DMAD affords 36 exclusively. The Royal Society of Chemistry 1999.

Benzopyrans. Part 23. Nitrogen Heterocycles Fused with or Linked to 1-Benzopyran from 3-Acyl-2-methyl-1-benzopyran-4-one

The enamine (2), prepared from the title benzopyranone (1; R2=H,Me,and Ph) and dimethylformamide dimehylacetal, on treatment with ammonia and hydroxylamine gives the fused pyridine (5) and pyridine-2-oxide (10), respectively.Hydrazine, phenylhydrazine, and guanidine undergo initial 1,6-addition to the enamine (2) ultimately giving the pyrazoles (14) and (15), and the pyrimidine (17), respectively.The pyridinioacetamidate (11), prepared from the enamine (2; R2=Me and Ph) and acetohydrazide, thermolyses to the fused pyridine (5).A refluxing ethanolic solution of the enamine (2; R2=Me and Ph) with ethyl glycinate forms the ester (18) which on treatment with ethanolic sodium ethoxide produces the azepine(20).