ChemInform Abstract: SCHNELLE REVERSIBLE WANDERUNG DER AROYLGRUPPE IN CIS‐O‐AROYL‐ACETYLACETONEN

Carbonotropy

“…Upon acylation of 1,3-diketones with acetyl chloride, an approximately 1 : 1 mixture of the Z (XLIX) and E (L) isomers is formed in almost all cases [90][91][92][93][94][95][96] so that the IH-NMR spectrum reflects, at low temperature, the signals of both isomers (Fig. 2.8).…”

“…A considerable reduction in the activation barrier of degenerate acyl migrations was achieved[80][81][82][83][84][85][86][87][88][89][90][91][92][93][94] is cis-(Z)-acylenols of 1,3-diketones XLVIII possessing the same structural moiety for the 1 ,5-shift of an acyl group as XLI. This fragment is present in the molecules of O-acetyl derivatives of naphthazarine XLI, which are characterized by slow intramolecular o ,= 0' -acetyl transfers(2.27) corresponding to a tautomeric equilibrium of very low mobility.…”