A reaction of tin(IV) bis o amidophenolate complex based on redox active 4,6 di tert butyl N (2,6 diisopropylphenyl) o aminophenol with various allyl halides was studied. This process includes the addition of 1 equiv. of allyl halide to the starting complex and is accompa nied by the change in the redox state of one of the redox active ligands. The reaction results in the formation of a new carbon-carbon bond between the allylic fragment and the carbon atom at position 5 of the ligand o iminoquinone ring, as well as a tin-halogen bond. The structure and composition of compounds synthesized were confirmed by ESR, NMR, and IR spectro scopy and elemental analysis.One of the most important problems of modern chem istry is the activation of the carbon-halogen bond in var ious chemical transformations with subsequent formation of new carbon-carbon or carbon-heteroatom bonds. At present, such processes are effected catalytically, mainly with the use of platinum group metal complexes. 1,2 The major role of these metal compounds in the reaction of the formation of new C-C bonds is due to the chemical spe cific features of the metal center, namely, its ability to undergo one step two electron oxidation and reduction. This property is a necessary condition in the C-C cou pling reactions, since the main catalytic steps such as oxi dative addition and reductive elimination are two elec tron processes.Introduction of redox active ligands capable of chang ing its own oxidation state in the coordination sphere of metals makes it possible to transfer the reaction center on the ligand, thus making the process of the C-C coupling indifferent to the nature of the metal center. Redox pro cesses are little characteristic of the nontransition metal derivatives, however, the scope of redox possibilities of this type metal compounds is considerably broadened in combination with the o quinone type ligands. The works 3,4 describe gallium and aluminum complexes with redox active diiminoacenaphthene ligand (BIAN) capa ble of activation of the CC triple bond in alkynes. Re cently, 5-7 it was found that metal complexes containing anions of the type (AP) 2 M -(AP is the dianionic form of various substituted o iminoquinones, M = Co, In) can activate carbon-halogen bonds in the reactions with var ious alkyl halides with subsequent formation of new carbon-carbon bonds.
Results and DiscussionIn the present work, we study a reaction of bis[4,6 di tert butyl N (2,6 diisopropylphenyl) o amidophenolato] tin(IV) tetrahydrofuratate (1) with various allyl halides. When a three fold excess of allyl halide is added to a solu tion of 1 in toluene, the reaction reaches completion with in three days at room temperature for allyl chloride, 24 h for allyl bromide, whereas in the case of allyl iodide the reaction is complete within several hours. In the course of the reaction, the color of the reaction mixture in all the cases changes from yellowish brown to deep red. Solid reddish brown crystalline compounds 2-4 (X = Cl, Br, I) were isolated from the reaction m...
