ИСТИНА

The heavier carbene analogs R2E (low-valent derivatives of Group 14 elements, E = Si, Ge, Sn, Pb) attract significant attention due to fundamental interest and to possible practical application. Such compounds are very reactive and usually highly unstable. The stabilization may be achieved kinetically (by introduction of sterically voluminous groups R), or thermodynamically (by using of special designed ligands R, possible to electronic interaction with E atom). In this report the synthesis, investigation of structure, studies of chemical and catalytic properties of a number of tetrylenes based on polydentate ligands are described. The ligands of various nature (differed in electronic and geometric characteristics of the substituents, donor atoms, rigidity) were used. It is shown that tetrylenes are effectively stabilized by ligands elaborated in our laboratory; the compounds obtained were used in the synthesis of different organometallic derivatives or as ligands for transition metal complexes. Furthermore, carbenes obtained used as initiators of ring-opening polymerization of lactones and may be characterized as very active catalysts giving target polymers with high control of the process. Book of Abstracts, O48.