Wyniki wyszukiwania - BazTech

Ograniczanie wyników

1 Wiadomości Chemiczne

1 2006

Znaleziono wyników: 1

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: hydroxyorganoboranes

Sortuj według:

Ogranicz wyniki do:

Kompleksy metali z ligandami boryloksylowymi

Luliński S., Serwatowski J.

Wiadomości Chemiczne

2006

[Z] 60, 7-8

467-486

The review deals with metal complexes bearing various types of boroxide ligands. It is divided into several chapters including synthesis, structural and spectroscopic (NMR) characterization followed by reactivity and catalytic properties of some novel compounds. Metal complexes with boroxide ligands can generally be defined as derivatives of hydroxydiorganoboranes R2BOH or dihydroxyorganoboranes RB(OH)2, where one or two hydrogen atoms are replaced with a metal. A few complexes with a closely related R,B2Oj ligand derived from triorganoboroxin [RBO]3 have also been included. Boroxide ligands may be regarded as electron defficient analogues of alkoxide ligands, due to specific electronic properties of a trivalent boron atom, which is able to interact by means of its 2p orbital with a lone electron pair of an adjacent oxygen atom. As a result of this so-called back-bonding, the B-O bond order is increased, whereas the ^-donor properties of oxygen are reduced. Accordingly, a metal oxygen bond is weakened. Another important point is that boroxides are sterically less crowding than bulky aryloxide ligands having comparable electronic properties. Hence, an increased reactivity of such complexes is expected, especially as catalysts or initiators in various polymerization processes.