Influence of the o-nitro group on base catalysis in nucleophilic aromatic substitution. Reactions in Benzene Solution.

Nucleophilic aromatic substitution reactions of 3-nitrophthalonitrile yield 3-hydroxyphthalonitrile and 3-neopentoxyphthalonitrile, the latter of which condensed to 1,8,15,22-tetraneopentoxyphthalocyanine as a mixture of isomers. Bisphthalonitriles such as 1,3-bis(2′,3′-dicyanophenoxy)-2,2-dipentylpropane, 1,3-bis(2′,3′-dicyanophenoxy)-2,2-diethylpropane, 1,3-bis(2′,3′-dicyanophenoxy)-2,2-dioctylpropane, and 1,3-bis(2′,3′-dicyanophenoxy)-2-methyl-2-trityloxymethylpropane all gave bis-crown-like 1,11,15,25-tetrasubstituted phthalocyanines as pure compounds when treated with lithium octoxide in 1-octanol at 196 °C. A host of nine other bisphthalonitriles including 1,5-bis(2′,3′-dicyanophenoxy)-3-oxapentane, 1,1-bis(2′,3′-dicyanophenoxymethyl)cyclohexane, 1,2-bis(2′,3′-dicyanophenoxymethyl)benzene, and 2,5-bis(2′,3′-dicyanophenoxymethyl)furan did not dimerize to mononuclear phthalocynaines. The "gem dimethyl" effect was suggested as a reason for the successful macrocyclizations. Key words: nucleophilic aromatic substitution, phthalonitriles, bisphthalonitriles, 1,11,15,25-tetrasubstituted phthalocyanines.

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Nucleophilic aromatic substitution reactions under phase-transfer conditions. Synthesis of alkyl aryl sulfides from isomeric dichlorobenzenes and thiolates

The Journal of Organic Chemistry ◽

10.1021/jo00152a039 ◽

1983 ◽

Vol 48 (4) ◽

pp. 604-605 ◽

Cited By ~ 18

Author(s):

Dario Landini ◽

Fernando Montanari ◽

Franco Rolla

Keyword(s):

Phase Transfer ◽

Nucleophilic Aromatic Substitution ◽

Aromatic Substitution ◽

Substitution Reactions ◽

Alkyl Aryl ◽

Aryl Sulfides

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Synthesis and fluorescent properties of N(9)-alkylated 2-amino-6-triazolylpurines and 7-deazapurines

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.15.41 ◽

2019 ◽

Vol 15 ◽

pp. 474-489 ◽

Cited By ~ 5

Author(s):

Andrejs Šišuļins ◽

Jonas Bucevičius ◽

Yu-Ting Tseng ◽

Irina Novosjolova ◽

Kaspars Traskovskis ◽

...

Keyword(s):

Nucleophilic Aromatic Substitution ◽

Secondary Amines ◽

Acetonitrile Solution ◽

Quantum Yields ◽

Cell Labelling ◽

Aromatic Substitution ◽

Fluorescent Properties ◽

Substitution Reactions ◽

Low Cytotoxicity ◽

Electron Donating Groups

The synthesis of novel fluorescent N(9)-alkylated 2-amino-6-triazolylpurine and 7-deazapurine derivatives is described. A new C(2)-regioselectivity in the nucleophilic aromatic substitution reactions of 9-alkylated-2,6-diazidopurines and 7-deazapurines with secondary amines has been disclosed. The obtained intermediates, 9-alkylated-2-amino-6-azido-(7-deaza)purines, were transformed into the title compounds by CuAAC reaction. The designed compounds belong to the push–pull systems and possess promising fluorescence properties with quantum yields in the range from 28% to 60% in acetonitrile solution. Due to electron-withdrawing properties of purine and 7-deazapurine heterocycles, which were additionally extended by triazole moieties, the compounds with electron-donating groups showed intramolecular charge transfer character (ICT/TICT) of the excited states which was proved by solvatochromic dynamics and supported by DFT calculations. In the 7-deazapurine series this led to increased fluorescence quantum yield (74%) in THF solution. The compounds exhibit low cytotoxicity and as such are useful for the cell labelling studies in the future.

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