Halogenation of N-substituted p-quinone imines and p-quinone oxime esters: III. Regioselectivity in the halogenation of N-aroyl(arylsulfonyl)oxyimino-2,5-cyclohexadienones

Avdeenko, A. P.; Konovalova, S. A.; Il'chenko, A. Y.; Glinyanaya, N. M.

doi:10.1134/s1070428006010106

Cited by 14 publications

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References 8 publications

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“…The properties of previously described compounds Ia [24], IIa, IIIa [25], IV [26], Va [27], VIa, VIb, VIIa, VIIb [28], IX, XIa, and XIb [9] were consistent with published data.…”

Section: Methodssupporting

confidence: 88%

Reaction of some N-substituted 1,4-benzoquinone imines with sodium arenesulfinates

2014

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N-Arylsulfonyl, N-aroyl, and N-[arylsulfonylimino(phenyl)methyl] derivatives of 1,4-benzoquinone imine reacted with sodium arenesulfinates to give 1,4-, 1,6-, and 6,1-addition products which were formed according to two concurrent paths: direct nucleophilic addition of arenesulfinate anion to neutral quinone imine molecule and radical ion addition of arenesulfinate radical to radical anion derived from quinone imine.We previously studied in detail reactions of N-aryl-2,6-dialkyl [1], N-aroyl, N-arylsulfonyl, N-[arylsulfonylimino(phenyl)methyl]-2,6(3,5, or 2,5)-dialkyl [2][3][4][5], and N-aryl(alkyl, trifluoromethyl)sulfonyl [6] derivatives of 1,4-benzoquinone imine with sodium arenesulfinates. Depending on the initial quinone imine structure, 1,4-, 6,3-, 1,6-, or 6,1-addition products were obtained. It was found that the reaction direction is determined not only by the nature of substituent on the nitrogen atom of quinone imine but also by the nature and position of substituents in the quinoid ring [4, 5]. 1,4-Benzoquinone imines having two alkyl substituents in the quinoid ring were mainly studied. We expected that reduction of the number of substituents in the quinoid ring should favor more accurate estimation of the effect of the N-substituent on the reaction direction. Therefore, the goal of the present work was to compare the reactivities of N-aroyl, N-arylsulfonyl, and N-[arylsulfonylimino-(phenyl)methyl] 1,4-benzoquinone imine derivatives containing no substituents in the quinoid ring or substituted at the 2-and/or 3-position toward sodium arenesulfinates.The reactions were carried out using excess sodium arenesulfinate (1 : 2) in acetic acid. The aryl groups in the quinone imine and arenesulfinate components were mainly p-methylphenyl and p-methoxyphenyl to facilitate signal assignment in the 1 H NMR spectra. In order to detect all products, we analyzed by 1 H NMR the precipitate before and after recrystallization and the product isolated from the mother liquor obtained after recrystallization. We thus succeeded in separating isomeric products and detecting compounds whose amount did not exceed a few percent.The results of the reactions of N-arylsulfonyl (IaIc, IIa-IIc, IIIa-IIIc, IV), N-aroyl (Va-Vc, VIa, VIb, VIIa, VIIb), and N-[arylsulfonylimino(phenyl)-methyl]-1,4-benzoquinone imines (VIIIa, VIIIb, IX, X, XIa, XIb) with sodium arenesulfinates XIIa-XIIc are shown in Scheme 1, and the product compositions (excluding reduced forms of quinone imines) are given in Table 1. Compounds Ia-Ic, IIa-IIc, IIIa-IIIc, and IV reacted mostly according to the 1,4-addition pattern, yielding amides XIIIa-XIIIc, XIVa-XIVc, XVaXVc, XVIa, and XVIb. Only the reaction of quinone imine IV having no substituents in the quinoid ring with sodium p-methoxybenzenesulfinate gave a mixture of 1,4-and 6,1-addition products XVIb and XXX.

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“…The properties of previously described compounds Ia [24], IIa, IIIa [25], IV [26], Va [27], VIa, VIb, VIIa, VIIb [28], IX, XIa, and XIb [9] were consistent with published data.…”

Section: Methodssupporting

confidence: 88%

Reaction of some N-substituted 1,4-benzoquinone imines with sodium arenesulfinates

2014

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“…The results are given in Scheme 1. Unlike N-arylsulfonyl-2,5-dialkyl-1,4-benzoquinone imines which took up one halogen molecule [2], the halogenation of N-aroyl-2,5-dialkyl-1,4-benzoquinone imines gave only several analogous cyclohexene compounds, namely N- (5,6- dimethyl-4-oxocyclohex-2-en-1-ylidene)benzamide (VII), N-(5,6-dibromo-2-isopropyl-5-methyl-4-oxocyclohex-2-en-1-ylidene)benzamides VIIIb and VIIIc, and N-(5,6-dibromo-3-isopropyl-6-methyl-4-oxocyclohex-2-en-1-ylidene)-4-nitrobenzamide (IX). Obviously, the corresponding 4-aroyliminocylohex-2-en-1-one derivatives are unstable due to effect of a strong electron-withdrawing substituent on the nitrogen atom (aroyl group), and they readily undergo dehydrohalogenation.…”

Section: N-aroyl-25-dialkyl-14-benzoquinone Imines I-iiimentioning

confidence: 99%

“…In the 1 H NMR spectra of N-aroyl-2,5-dialkyl-1,4-benzoquinone imines, differences in the chemical shifts of protons in the quinoid ring were considerably smaller than those observed for analogous N-arylsulfonyl derivatives; therefore, assignment of signals in the spectra of compounds I-III was more difficult. The 3-H proton in I-III resonated in the 1 H NMR spectra in the region δ 6.58-6.66 ppm, while the 6-H signal was located at δ 6.44-6.59 ppm; the corresponding signals of N-arylsulfonyl derivatives appeared in the regions δ 7.89-7.96 and 6.50-6.64 ppm, respectively [2]. …”

mentioning

confidence: 98%

“…We previously examined halogenation of N-arylsulfonyl-2,5-dialkyl-1,4-benzoquinone imines [2] and found that the main factors determining the direction of addition of halogen molecule are the size of substituents in the quinoid ring and the size of the halogen atom. The presence of a strong electron-withdrawing substituent on the nitrogen atom, in particular aroyl group, also considerably affects the halogenation process [1,3,4].…”

mentioning

confidence: 99%

“…As substrates we used N-aroyl-1,4-benzoquinone imines which, like N-arylsulfonyl derivatives studied previously [2], contained different alkyl substituents (i-Pr, Me) in positions 2 and 5 of the quinoid ring: N-aroyl-2,5-dimethyl-, -2-isopropyl-5-methyl-, and -5-isopropyl-2-methyl-1,4-benzoquinone imines Ia-Ic, IIa-IIc, and IIIa-IIIc, and their reduction products, 4-amino-N-aroyl-2,5-dimethyl-, 2-isopropyl-5-methyl-, and -5-isopropyl-2-methylphenols IVa-IVc, Va-Vc, and VIa-VIc.…”

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Halogenation of N-substituted p-quinone monoimines and p-quinone monooxime esters: X. Halogenation of N-aroyl-2,5(2,3)-dialkyl-1,4-benzoquinone monoimines and their reduction products

2009

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Introduction of a strong electron-withdrawing substituent to the nitrogen atom of 2,5(2,3)-dialkyl-1,4-benzoquinone imines makes their halogenation products, the corresponding cyclohexene derivatives, very unstable and favors halogenation of methyl groups in the quinoid ring. Bromination of 4-amino-N-aroyl-2,5-dialkyl-6-bromophenols gave 2,5-dialkyl-6-benzoyloxy-3,5-dibromocyclohex-2-ene-1,4-diones. * For communication IX, see [1].We previously examined halogenation of N-arylsulfonyl-2,5-dialkyl-1,4-benzoquinone imines [2] and found that the main factors determining the direction of addition of halogen molecule are the size of substituents in the quinoid ring and the size of the halogen atom. The presence of a strong electron-withdrawing substituent on the nitrogen atom, in particular aroyl group, also considerably affects the halogenation process [1, 3,4]. Halogenation of N-aroyl-2,5(2,3)-dialkylsubstituted 1,4-benzoquinone imines and their reduction products, N-aroyl-2,5(2,3)-dialkyl-4-aminophenols was not reported previously.The goal of the present work was to study halogenation of N-aroyl-2,5(2,3)-dialkyl-1,4-benzoquinone imines, elucidate specific features of the halogenation process, and compare these reactions with halogenation of the corresponding N-arylsulfonyl derivatives. As substrates we used N-aroyl-1,4-benzoquinone imines which, like N-arylsulfonyl derivatives studied previously [2], contained different alkyl substituents (i-Pr, Me) in positions 2 and 5 of the quinoid ring: N-aroyl-2,5-dimethyl-, -2-isopropyl-5-methyl-, and -5-isopropyl-2-methyl-1,4-benzoquinone imines Ia-Ic, IIa-IIc, and IIIa-IIIc, and their reduction products, 4-amino-N-aroyl-2,5-dimethyl-, 2-isopropyl-5-methyl-, and -5-isopropyl-2-methylphenols IVa-IVc, Va-Vc, and VIa-VIc.Due to the presence of a methyl or isopropyl group in the ortho position with respect to the imino nitrogen atom, quinone imines I-III in solution exist as a single isomer, which is confirmed by the 1 H NMR data. In the 1 H NMR spectra of N-aroyl-2,5-dialkyl-1,4-benzoquinone imines, differences in the chemical shifts of protons in the quinoid ring were considerably smaller than those observed for analogous N-arylsulfonyl derivatives; therefore, assignment of signals in the spectra of compounds I-III was more difficult. The 3-H proton in I-III resonated in the 1 H NMR spectra in the region δ 6.58-6.66 ppm, while the 6-H signal was located at δ 6.44-6.59 ppm; the corresponding signals of N-arylsulfonyl derivatives appeared in the regions δ 7.89-7.96 and 6.50-6.64 ppm, respectively [2]. N-Aroyl-2,5-dialkyl-1,4-benzoquinone imines I-IIIwere synthesized by oxidation of the corresponding aminophenols IV-VI with lead tetraacetate in acetic acid. The chlorination of quinone imines I-III and aminophenols IV-VI was performed using gaseous chlorine, and the bromination was carried out with molecular bromine in CHCl 3 , AcOH, DMF, or DMFAcOH (1 : 5) at different substrate-to-reagent ratios under different temperature conditions. The results are given in Scheme 1. Unlike N-a...

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Halogenation of N‐Substituted p‐Quinone Imines and p‐Quinone Oxime Esters. Part 3. Regioselectivity in the Halogenation of N‐Aroyl(arylsulfonyl)oxyimino‐2,5‐cyclohexadienones.

et al. 2006

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Quinone derivatives Q 0410Halogenation of N-Substituted p-Quinone Imines and p-Quinone Oxime Esters. Part 3. Regioselectivity in the Halogenation of N-Aroyl(arylsulfonyl)oxyimino-2,5-cyclohexadienones. -Halogenation of title p-quinone oxime esters like (I) and (VI) is determined by the N-substituent and the geometry of oxime double bond. It is shown that no E/Z-isomerization takes place under the reaction conditions. -(AVDEENKO, A. P.; KONOVALOVA, S. A.; IL'CHENKO, A. Y.; GLINYANAYA, N. M.; Russ. J. Org. Chem. 42 (2006) 1, 56-65; Donbass State Mach. Build. Acad., Kramatorsk 343913, Ukraine; Eng.) -Mischke 39-099

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Halogenation of N-substituted p-quinone imines and p-quinone oxime esters: III. Regioselectivity in the halogenation of N-aroyl(arylsulfonyl)oxyimino-2,5-cyclohexadienones

Cited by 14 publications

References 8 publications

Reaction of some N-substituted 1,4-benzoquinone imines with sodium arenesulfinates

Reaction of some N-substituted 1,4-benzoquinone imines with sodium arenesulfinates

Halogenation of N-substituted p-quinone monoimines and p-quinone monooxime esters: X. Halogenation of N-aroyl-2,5(2,3)-dialkyl-1,4-benzoquinone monoimines and their reduction products

Halogenation of N‐Substituted p‐Quinone Imines and p‐Quinone Oxime Esters. Part 3. Regioselectivity in the Halogenation of N‐Aroyl(arylsulfonyl)oxyimino‐2,5‐cyclohexadienones.

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