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The facile C–C coupling reaction of activated forms of azaaromatics (azine-N-oxides) with cymantrenyl lithium, as a nucleophile, has first been carried out. It has been established that aromatization of intermediate adducts can be realized through either oxidative or eliminative pathways, depending on the structure of the starting azine N-oxide. In particular, the dihydroazinyl intermediates, bearing the additional N(4)-atom relative to the N-oxide group, proved to undergo aromatization through the eliminative pathway. The X-ray studies of 3,6-diphenyl-1,2,4-triazine-5-yl-cymantrene have revealed that it is crystallized in both orthorhombic and monoclinic forms. © 2018 Elsevier B.V.

Novel complexes of 1,2-P,N-bidentate ferrocenyl ligands with AgOAc or with [RuCl2(PPh3)3] as catalysts have been studied in asymmetric synthesis. The catalytic activity of these systems have been studied in [3+2]-cycloaddition of azomethine ylides with olefins and the asymmetric transfer hydrogenation of ketones.

Two synthetic routes to the chiral azinylferrocenes (CAFs) 5 and 15, key intermediates for the synthesis of new enantiomerically enriched P,N-ligands, have been compared. The first approach is based on the palladium-catalyzed cross-coupling reaction of halogenated azines with organozinc derivatives of ferrocenes (the Negishi reaction). The second approach exploits a new synthetic methodology, which provides a shorter pathway, through the direct C–H functionalization of aromatics by the C–C coupling of halogen-free (hetero)arenes with lithium ferrocenes bearing stereogenic C and S atoms. The palladium complexes of P,N-ligands have been used as catalysts for the Tsuji–Trost reaction, which proceeds with high enantioselectivity to give allylic substitution products in good yields.