

ON THE QUESTION OF SELECTIVE PROTOCOL FOR THE PREPARATION OF JUGLONE via (4+2) CYCLOADDITION INVOLVING 3-HYDROXYPYRIDAZINE: DFT MECHANISTIC STUDY

Abstract
The possibility of preparation of juglone via Diels–Alder reaction of 3-hydroxypyridazine and 2-nitroquinone was analyzed on the basis of DFT computational study. It was found that key stage of the proposed transformation is head-to-head, polar cycloaddition process, which is realized without formation of zwitterionic intermediate. Further transformations of the intermediate exhibit nature of pseudocyclic reactions with nonconcerted reorganization of the electron density.
Keywords
3-hydroxypyridazine; juglone, (4+2) cycloaddition; mechanism; molecular electron density theory.
Latvian Institute of Organic Synthesis - Aizkraukles iela, 21, Riga, LV-1006, Latvia - hgs@osi.lv