2-Ethoxy-3,4-dihydro-l,2-pyrane

ETHOXY DIGLYCOL see CBROOO 2-ETHOXY DIHYDROPYRAN see EER500 2-ETHOXY-3,4-DIHYDRO-l,2-PYRAN see EER500 2-ETHOXY-3,4-DIHYDRO-2H-PYRAN see EER500 2-ETHOXY-2,3-DIHYDRO-y-PYRAN see EER500 6-ETHOXY-l,2-DIHYDRO-2,2,4-TRIMETHYLQUINOLINE see SAVOOO 1-ETHOXY-3,7-DIMETHYL-2,6-OCTADIENE see GDGIOO... 

ETHOXY-3,4-DIHYDRO-l,2-PYRAN or 2-ETHOXY-3,4-DIHYDRO-2h-PYRAN (103-75-3) Forms explosive mixture with air (flash point 108°F/42°C oc). Violent reaction with strong oxidizers. Incompatible with strong acids, nitrates. 

SYNS 2-ETHOXY-2.3-DIHYDRO-Y-PYRAN 2-ETHOXY-3,4-DIHYDRO-l,2-PYR.- N 2-ETHOXY-3.4-DIHYDRO-2H-PYRAN... 

However, when 36 was heated with a-amino heterocycles or with cyclic 1,3-dicarbonyl or potential 1,3-dicarbonyl compounds, 3-heteroarylp)rr-azol derivatives were obtained. In this manner 36 afforded, when heated with 2-aminopyridine and 3-amino-lH-pyrazol in acetic acid under reflux for 2 h and 5 h, respectively, 3-(5-ethoxy-l-phenyl-lH-pyrazol-3-yl)-4H-pyrido[l,2-fl]pyrimid-4-one (38) and 6-(5-ethoxy-l-phenyl-lH-p5rrazol-3-yl)pyrazolo[l,5-fl]pyrimid-7(lH)-one (39) in 70% and 77% 5deld, respectively. Similarly, 36 afforded with cyclicjS-dicarbonyl compounds, such as 4-hydroxy-6-methyl-2H-pyran-2-one and 5,5-dimethylcyclohexane-l,3-dione by heating in acetic acid for 4 h and 8 h, respectively, the corresponding 3-(5-ethoxy-l-phenyl-lH-pyrazol-3-yl)-7-methyl-2H,5H-pyrano[4,3- 7]pyran-2,5-dione (40) and 3-(5-ethoxy-l-phenyl-IH-pyrazol-3-yl)-7,7-dimethyl-7,8-dihydro-2H-chromene-2,5-dione (41) in 26% and 82% yield, respectively (Scheme 15). 

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