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The electrochemical behavior of 5 1h pyrromethenones and 3 4 dihydro 5 1h pyrromethenones

Monatshefte fuer Chemie 116(5): 681-684

The electrochemical behavior of 5 1h pyrromethenones and 3 4 dihydro 5 1h pyrromethenones

Cyclic voltammetry and polarography measurements in anhydrous dimethylformamide indicate that 1,3,4,5-tetrahydro-3-methoxycarbonylmethyl-3',4,4,4'-tetramethyl-5-oxo-2,2'-pyrromethen-5'-carboxylic acid tert-butylester [a 3,4-dihydro-5(1H)-pyrromethenone] is both easier to reduce and to oxidize than structurally related 5(1H)-pyrromethenones.

Accession: 006670331

Related references

Gossauer, A.; Blacha-Puller, M., 1981: Syntheses of bile pigments 13. preparation of 3 4 di hydro 5 1h pyrromethenones from 5 1h pyrromethenones and from 5 2h di pyrryl methanones. 5(2H)-Dipyrrylmethanones 2 which are usually obtained by catalytical hydrogenation of 5(1H)-pyrromethenones are only formed as the main product (.apprx. 80%) in alkaline solutions. In the absence of base, the obtained mixture contains up to 40% of...

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