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The mechanism of intermediate formation in the reaction of HAlBu i 2 with Cp 2 ZrCl 2 has been studied by DFT calculations. Stationary points have been localized on the potential energy surface of the reaction; enthalpy has been calculated for each of them at T ) 203 K. It was shown that the thermodynamically probable way of the process includes formation of a bridge bimetallic complex [Cp 2 ZrCl 2 • HAlBu i 2 ], which with dissociation gives Cp 2 ZrHCl. The subsequent coordination of Cp 2 ZrHCl with HAlBu i 2 provides the intermediate [Cp 2 ZrHCl • HAlBu i 2 ], which dimerizes into an experimentally observed complex [Cp 2 ZrH 2 • ClAlBu i 2 ] 2 . The competing stage of [Cp 2 ZrHCl • HAlBu i 2 ] interaction with HAlBu i 2 yields complex [Cp 2 ZrH 2 • ClAlBu i 2 • HAlBu i 2 ], which shows low activity in the olefin hydrometalation. As a result, the scheme of the intermediates' formations and transformations in the reaction of HAlBu i 2 with Cp 2 ZrCl 2 was proposed.

An efficient method for the synthesis of new spirotetraoxadodecanediamines and tetraoxazaspirobicycloalkanes has been developed by reactions of primary arylamines with gem-dihydroperoxides and α,ω-dialdehydes catalyzed by lanthanide catalysts.

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