Reaction of 2,2,3,3-Tetracyanocyclopropanecarboxylic Acid with Iodides. Synthesis of 3-Cyano-4-dicyanomethylidene-5-oxo-4,5-dihydro-1H-pyrrol-2-olates

Abstract

Reactions of 2,2,3,3-tetracyanocyclopropanecarboxylic acid with potassium, sodium, calcium, strontium, barium, ammonium, N-methylpyridinium, N-methylquinolinium, N,N-dimethyl-1,4-diazabicyclo-[2.2.2]octane-1,4-diium, and N,N-dimethylanilinium iodides afforded the corresponding 3-cyano-4-dicyanomethylidene-5-oxo-4,5-dihydro-1H-pyrrol-2-olates. Scheme 1.

The luminescent properties of structures built from 3-cyano-4-dicyanomethylene-5-oxo-4,5-dihydro-1H-pyrrole-2-olate and copper(I,II) cations

“…We synthesized six new salts based on the 3-cyano-4-dicyanomethylene-5-oxo-4,5-dihydro-1H-pyrrole-2-olate anion (HA À ) with Cu 2+ and Cu + cations, namely { [Cu II (HA) (6). The crystal structures of 1-6 were determined by single crystal X-ray diffraction.…”

“…Fig.8The arrangement of the anionic dimers in the ribbons in complex 4. The N3A iii /C8 distance is 3.421(6) A. Adjacent ribbons are connected by p-p stacking interactions, forming an anionic wall.…”

Synthesis of 2,2,3,3-tetracyanocyclopropyl ketones and their reactions with oxygen-centered nucleophiles

“…However, the scope of this procedure is essentially limited: it cannot be used for the synthesis of tetracyanocyclopropanes having five or six electronwithdrawing substituents. Potassium iodide is capable of reacting with cyclopropanes, leading to cleavage of the three-membered ring with formation of cyano-substituted propenides [5][6][7][8].…”

“…It is known that electron-deficient cyclopropanes having four and more electron-withdrawing groups exhibit high reactivity toward nucleophiles [5][6][7][8][11][12][13][14][15][16][17]. The direction and depth of their transformations in reactions with nucleophiles are largely determined by the nature of nucleophile and electron-withdrawing groups in the substrate.…”

“…Two main reaction directions are usually considered. The first of these involves initial attack by nucleophile on carbon atoms in the three-membered ring, leading to opening of the latter [5][6][7][8], while the second begins with attack on electronwithdrawing group (carbonyl or cyano), and such reactions often occur with conservation of the cyclopropane ring [11][12][13][14][15].…”