HOMOALLENYLAZINES - INTRAMOLECULAR CRISSCROSS ADDITION SUBSTRATES - SYNTHESIS, STRUCTURE AND CONFORMATIONAL STUDY

Preparation of some new 2,2-dimethylpenta-3,4-dienal azines starting b y Claisen-Cope rearrangement in pyrolysis of the corresponding acetals and followed by condensation reactions of homoallenylaldehydes so for med with hydrazin hydrate is described. Non-symmetrical azines were pr epared from the diethylphosphorohydrazidate by the reaction with homoa llenylaldehydes. Allenyliden-diethylphosphoro-hydrazidate so formed ga ve after reaction with NaH and following condensation with homoallenyl aldehyde corresponding non-symmetrical azine. New compounds are charac terized by MS, IR H-1 and C-13 NMR spectroscopy. The assignment of the NMR signals is based on HSQC and HMBC pulse sequences. A conformation al analysis was carried out using AM1 method. X-ray structural analysi s of 3-benzyl-2,2-dimethylpenta-3,4-dienal azine is presented.