Suzuki arylation of 2‐halogeno and 2,7‐dihalogeno derivatives of 1,8‐bis(dimethylamino)naphthalene (proton sponge) was carried out. It was shown that the sterically hindered nature of the starting compounds in combination with the enhanced reactivity of their peri‐NMe2 groups allow to obtain the target 2‐aryl and 2,7‐diaryl derivatives in 20–34 % yields only. In most cases, a tandem Pd‐catalyzed hydrodehalogenation/N‐demethylation process was predominant. The latter, however, makes it possible to obtain yet unknown and synthetically valuable 2‐aryl‐N1,N1,N8‐trimethyl‐1,8‐diaminonaphthalenes (21–50 %), which can be easily converted into the corresponding proton sponges by conventional N‐methylation. Using the literature data on 2,7‐disubstituted derivatives of the proton sponge as a background together with the XRD and basicity measurements performed in this work, a comprehensive analysis of the so‐called “buttressing effect” in 2‐aryl‐ and 2,7‐diaryl‐1,8‐bis(dimethylamino)naphthalenes, along with previously unknown 2,6‐diphenyl‐N,N‐dimethyl‐p‐toluidine has been carried out for the first time.

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4-Bromo- and 4,5-dibromo-1,8-bis(dimethylamino)naphthalenes were arylated with arylboronic acids under Suzuki reaction conditions to provide 4-aryl- and 4,5-diaryl-1,8-bis(dimethylamino)naphthalenes, respectively. The interaction of 4,5-dibromo-1,8-bis(dimethylamino)naphthalene with pyridin-3-ylboronic acid was accompanied by heterocyclization leading...

Diarylnaphthalenes are a fascinating example of strained organic molecules that have found many practical applications due to unusual parallel face-to-face arrangement of two periaryl rings in close proximity almost perpendicular to the central naphthalene backbone. 1,8-Diarylnaphthalenes show notable potential as photoluminescent and chiral sensors, stereodynamic switches, nonlinear optic chromophores, blue-transparent frequency doublers, materials for creating high-performance blue and green OLEDs, chiral ligands and so on. Molecules of this type have also been used as convenient models for studying π-π, dipole-π and cation-π interactions. 1,8-Diarylnaphthalenes are also interesting as objects to study atropisomeric transformations: if the peri-aryl rings have ortho-or metasubstituents, then the anti-conformer becomes C 2 -symmetrical (hence chiral), and the syn-isomer upon symmetrical substitution is achiral. In this review, data on synthetic methods, applications, atropisomerism and structural characteristics of 1,8-diaryl-and 1,8-dihetarylnaphthalenes are summarized.

1,3-Dipolar Cycloaddition of Acetonitrile Oxide to ∆ 23 -20-Hydroxysteroids.-Cycloaddition of acetonitrile oxide, generated in situ from aldoxime (IV), to the title steroidic alkenes (III) and (VII) affords a 1:1 mixture of diastereomeric isoxazolines (V) and (VIII), resp., demonstrating that the β-hydroxy group (in contrast to the previously studied steroidic α-hydroxyalkenes) has no influence on the stereochemical outcome of the reaction. -(LITVINOVSKAYA, R. P.; DRACH, S. V.; ERMOLENKO, E. A.; KHRIPACH, V. A.; Zh.