Experimental and computational study on the reactivity of 2,3-bis[(3-pyridylmethyl)amino]-2(Z)-butene-1,4-dinitrile, a key intermediate for the synthesis of tribenzoporphyrazine bearing peripheral methyl(3-pyridylmethyl)amino substituents

Abstract

An earlier developed alkylating path leading to tetraalkylated diaminomaleonitrile derivatives was explored. Attempts to explain the reactivity of the representative dialkylated diaminomaleonitrile 2,3-bis[(3-pyridylmethyl)amino]-2(Z)-butene-1,4-dinitrile during the alkylation reaction were performed using X-ray and density functional theory (DFT) studies. The condensed Fukui functions accompanied by softness indices were found to be useful in explaining its reactivity observed during the reaction. The values of the Fukui functions and condensed softness for electrophilic attack calculated from Mulliken, Löwdin, and natural population analyses closely corresponded to the experimental observations. When 2,3-bis[(3-pyridylmethyl)amino]-2(Z)-butene-1,4-dinitrile disodium salt was treated with dimethyl sulfate at lower temperatures the alkylation reaction prevailed, whereas at higher temperatures the alkylating agent acted as a hydride anion acceptor, which favored the elimination reaction. The tetraalkylated dinitrile 2,3-bis[methyl(3-pyridylmethyl)amino]-2(Z)-butene-1,4-dinitrile was used in the synthesis of tribenzoporphyrazine bearing methyl(3-pyridylmethyl)amino groups, which was subsequently subjected to solvatochromic and metallation studies. The changes observed during metallation seem to result from the coordination of the 3-pyridyl group by a palladium ion. This could influence the configuration of the methyl(3-pyridylmethyl)amino moiety, causing more effective donation of a lone pair of electrons from peripheral nitrogen to the macrocyclic ring.Graphical abstract.Electronic supplementary materialThe online version of this article (doi:10.1007/s00706-011-0503-9) contains supplementary material, which is available to authorized users.

Magnesium porphyrazine with peripheral methyl (3,5-dibromophenylmethyl)amino groups – synthesis and optical properties

“…Herein we report the synthesis and characterization of porphyrazine bearing peripheral methyl(3,5-dibromophenylmethyl)amine groups in the periphery. This study is an extension of our previous report [6] on the unusual reactivity and applications of diaminomaleonitrile in the synthesis of porphyrazine systems. The aminoporphyrazines and seco-dimethylaminoporphyrazines have been extensively studied as photosensitizers in the photodynamic therapy of cancer and as robust catalysts for highly efficient endoperoxide synthesis [11,16].…”

“…amino]-3-[(3,5-dibromophenylmethylidene)amino]-2(Z)butene-1,4-dinitrile (4) and 2,3-bis[(3,5-dibromophenylmethyl)amino]-2(Z)-butene-1,4-dinitrile (5). Our previous study on the alkylation reaction with dimethyl sulfate of dialkylated diaminomaleonitrile substrates, indicated the prevalence of the alkylation reaction after treating dialkylated derivative as disodium salt with dimethyl sulfate at lower temperatures, whereas at higher temperatures the alkylating agent acted as a hydride anion acceptor, which favored the elimination reaction to imine 2-[(3-pyridylmethyl)amino]-3-[(3-pyridylmethylidene)amino]-2(Z)-butene-1,4-dinitrile with 45% yield [6]. To avoid this unwelcome process in our study, the alkylation reaction of dialkylated derivative 5 to tetralkylated derivative 6 was performed in DMF with methyl iodide (in the presence of cesium carbonate as a base at 40°C for 24 h) by adapting the procedure of Fuchter et al [4].…”

“…In recent years, diaminomaleonitrile (DAMN) and its derivatives have been applied in the synthesis of many heterocyclic compounds, including imidazoles, pyrazines, pyrimidines, purines, azepines, pyrroles, oxazoles, nucleosides as well as porphyrazine macrocycles [1][2][3][4][5][6][7][8][9][10]. At present, after many years of research, porphyrazines (Pzs) substituted with nitrogen atoms in the β positions or having rings bound to both β,β positions form a distinct class of novel macrocycles (aminoporphyrazines), along with other porphyrazines substituted with sulphur, oxygen, alkyl or aryl residues [11][12][13][14].…”

“…Lately, our group has studied porphyrazines substituted in the periphery with methyl(3-pyridylmethyl)amino, 2,5-dimethylpyrrolyl substituents, dimethylamino, 2,5-dimethylpyrrol-1-yl, 2,5-dithienylpyrrol-1-yl, 2,5-di(biphenyl-4-yl)pyrrol-1-yl and 2-(1-adamantyl)-5-phenylpyrrol-1-yl moieties [17][18][19][20][21][22][23]. Moreover, an earlier developed alkylation path [1,4,15] leading to tetraalkylated diaminomaleonitrile substrates for Pzs synthesis has been explored [6]. The reactivity of therein described dialkylated diaminomaleonitrile representative, 2,3-bis[(3-pyridylmethyl)amino]-2(Z)-butene-1,4-dinitrile, has been analyzed by using X-ray and DFT studies.…”

A new nano‐sized mononuclear Cu (II) complex with N,N‐donor Schiff base ligands: sonochemical synthesis, characterization, molecular modeling and biological activity

“…Diaminomaleonitrile (DAMN, N 4 C 4 H 4 ) and its corresponding compounds have benefited from many advantages owing to their potential wide applications and structural diversity such as synthesis of many from the amino and imine compounds . N 4 C 4 H 4 is one of the specific chemical material in the field of chemistry, especially organic chemistry, used as the raw material for producing a wide range of combinations .…”