Investigation of the products of interaction of cyclic diketones with nitrogen-containing 1,4-binucleophiles

Abstract

In cyclic 1,5-diketones the position of the carbonyl groups determines exclusively the ease of their cyclization and makes them as convenient basis for the synthesis of nitrogen-, oxygen-, and sulfur-containing heterocycles [1,2].The aim of the present work is the study of the reactivity of the Michael adducts 1a-j [3,4], obtained from dimedone and aromatic aldehydes or furfural (adduct 1j), in relation to the bidentatic nucleophiles o-phenylenediamine 2 and o-aminophenol 3. The cyclic tetraketones 1a-j exist in the enolic form which makes them structurally close to α,β-unsaturated ketones, the reactivity of which in relation to 1,4-dinucleophiles has been studied previously [5,6].The electronic character of the substituents in R influence the direction of the interaction of compounds 1a-i with o-phenylenediamine 2 on boiling these reactants in 2-propanol (method A). The corresponding hexahydrodibenzodiazepinones 4a-f were obtained from tetraketones 1a (R = Ph) and 1b-f (electronwithdrawing substituents in R: 4-F, 4-Cl, 4-Br, 4-NO 2 ).When electron-donating substituents (4-OMe, 4-NMe 2 , 2-OH) are present in R, as in compounds 1g-i, either decomposition of the latter takes place (in the case of tetraketones 1g,h) with the formation of the corresponding azomethines 5a,b, or conversion into decahydroacridinedione 6 occurs (from tetraketone 1i). Hexahydrodibenzodiazepinone 4j is obtained from hetaryl-substituted tetraketone 1j (R = 2-furyl).Tetraketones 1a-d,g,h do not react with o-aminophenol 3 under the conditions mentioned above (method A). Only on boiling these reactants in DMF the interaction products, decahydroacridinediones 7a-f, were obtained in good yield.The results obtained enable the interaction of compounds 1 with binucleophiles 2 and 3 to be represented in the following way.

Aroyl[bis(4-hydroxycoumarin-3-yl)]methanes in reactions with 1,2-diaminobenzenes

“…Earlier, 7 we have demonstrated that the reaction of aryl(aroyl)[bis(5,5 dimethyl 1,3 dioxocyclohexan 2 yl)]methanes with o phenylenediamine (o PDA) produces hexahydrobenzo[b,e] 1,4 diazepin 1 one derivatives 1A or 9 aryl(aroyl) 10 (2 aminophenyl)decahydroacridine 1,8 dione derivatives 2 depending on the electronic char acter of the substituent in the aryl or aroyl fragments. Electron withdrawing substituents in the aromatic moi ety facilitate the formation of the diazepine ring, whereas the formation of acridones is typical of the starting polyketones containing electron releasing substituents in the benzene ring.…”

The synthesis of novel hexahydrodibenzo[b,e][1,4]diazepin-1-one derivatives

“…The composition and structure of diazepinones 5a-r have been proved via elemental analysis, 1 H, 13 C NMR spectroscopy and in some cases mass spectrometry data. The presence of molecular ion peaks of low intensity and also fragmentary ion signals corresponding to the masses of dibenzodiazepine (highest in intensity) and aroyl fragments was common for all mass spectra of hexahydrodibenzo [b,е] The signals of all proton-containing fragments are present in 1 H NMR spectra of compounds 5a-p.…”

“…The methylen proton and iminogroup proton in diazepinones 5a-r interact with each other which leads to a doublet in the spectra (J 5.0 Hz). In 13 C NMR spectra of compounds 5e,f,h-j,m all the necessary carbon signals are present, and using the DEPT-135 procedure allows us to identify the signals of secondary and tertiary carbon atoms.…”

“…6,7 Also partially hydrogenated dibenzodiazepines obtained from 3-aminoenones of cyclohexene-1,3-dione and aldehydes were described in references 8-12. As we showed earlier, 13 adducts of dimedone and aromatic aldehydes depending on the electronic properties of the substituent in the reaction with o-phenylenediamine (o-PDA) form either 11-arylhexahydrodibenzo[b,е][1,4]-diazepin-1-ones (1, R = Ar) or decahydroacridinones (2, R = Ar). Diazepines 1 were also obtained via one-pot condensation 13 by sequential addition of reagents, namely: by reflux of dimedone with o-PDA in 2-propanol in the presence of a catalytic amount of acetic acid for 40 minutes followed by the addition of aldehyde.…”

“…As we showed earlier, 13 adducts of dimedone and aromatic aldehydes depending on the electronic properties of the substituent in the reaction with o-phenylenediamine (o-PDA) form either 11-arylhexahydrodibenzo[b,е][1,4]-diazepin-1-ones (1, R = Ar) or decahydroacridinones (2, R = Ar). Diazepines 1 were also obtained via one-pot condensation 13 by sequential addition of reagents, namely: by reflux of dimedone with o-PDA in 2-propanol in the presence of a catalytic amount of acetic acid for 40 minutes followed by the addition of aldehyde. We have reported the synthesis of two compounds of the 11-aroylhexahydrodibenzo[b,е] [1,4]diazepin-1-ones series (R = COAr), when arylglyoxals were used instead of benzaldehydes.…”