Reaction of α,β-unsaturated ketones with tetracyanoethylene

An unexpected bicyclic pyrrolidinedione by rearrangement of the β-lactam ring under basic conditions

“…There is one molecule in the asymmetric unit and the N-O distances found are on the same order as those reported for other compounds with similar fragments. 5,6 In fact, the N( The molecules in the crystal structure are linked by intermolecular N-H···O and C-H···O hydrogen bonding (Table 2), as represented in Figure 2. The packing is stabilized by intermolecular N1-H1N···O7 and C2-H2···O7 hydrogen bonds (dotted light blue lines), which lead to endless associated molecular chains running along the [010] direction.…”

Reaction of tetracyanocyclopropyl ketones with hydrazine hydrate

“…The reaction is completed by the addition of the amide group to the amidine fragment of intermediate D. Similar conversions are usual for the polycyano substances where the hydroxy and nitrile groupd are spatially close. It results as a rule in the formation of 2-iminofurane fragment and when therewith the oxygen atom of the furan ring is adjacent to the atom bearing the proton-containing nitrogen heteroatom (as in intermediate C) always further recyclization occurs into a pyrrole ring [12][13][14][15]. Yet if this recyclization is initiated by a reagent of basic character, in some cases decyclization is observed and the subsequent cyclization at the vicinal cyano group [16,17], namely, the process is analogous to the path we suggested for the conversion Fig.…”

Reactions of pregnenolone and 16-dehydropregnenolone acetate with tetracyanoethylene

“…Structure A possesses a CH acid center and endocyclic double bond at the carbonyl group, and intramolecular Michael addition gave rise to cyclohexane fragment in final pentacyclic compound II. Analogous transformations of α,β-unsaturated ketones with a simpler structure were described in [7,8].…”