118399-52-3Relevant academic research and scientific papers
Tautomerism of O-Alkylidenepropanedinitrile and O-Alkylidenecyanamide Groups in O-Substituted Acetylacetones
Hartke, Klaus,Richter, Wolfgang F.,Kaempchen, Thomas
, p. 669 - 676 (2007/10/02)
Reaction of the sodium salt of acetylacetone (1)with (α-chlorobenzylidene)propanedinitrile (2, R = Ph) leads to the C-substitution product 4 as the cis-enol.The trans-enol 5 is only obtained as an intermediate (e.g. photochemically) yielding immediately the 2-pridone 6.Acetylacetone (7) as such reacts with 2 (R = Ph) or with N-cyanobenzimidoyl chloride (9) in the presence of triethylamine/DMAP to give the O-substitution products 8 and 10 as mixtures of their E/Z-isomers.The Z-isomers show a rapid degenerate (O->O) migration.By heating, 8Z rearranges irreversibly to the benzoic acid enol ester 11. 3-Phenylacetylacetone or its thallium(Iy) salt 16 reacts with (1-chloroalkylidene)propanedinitriles 2 or with N-cyanobenzimidoyl chloride (9) to yield the O-substitution products 14, 15, 17a, and 17b. 8Z, 17a, and 17b were investigated by DNMR spectroscopy. - Keywords: Acetylacetonates, O-substituted/ (Alkenyloxymethylene)cyanamide derivatives/ (Alkenyloxymethylene)propanedinitrile derivatives/ Tautomerism
