Research

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Two main areas of research are being pursued at present:

(i) synthesis, characterization and evaluation of new compounds with low valent group 14 donor atoms, and

(ii) coordination chemistry of a variety of multidentate amine, thiolato and hydroxo ligands with transition metal ions.

Projects concerned with low valent group 14 donor systems ranges from complexes of polydentate isocyanid ligands across metal stabilized 1-H/R-benzoxazolin-2-ylidene and 1,3-di-H/R-benzimidazolin-2-ylidene ligands to stable free carbens and stannylenes. Improvement of catalytic transformations (e. g. replacement of phosphines of CO in classical catalysts with nucleophilic carbenes or isocyanides) and development of electro-optical devices constitute the driving force for research in this area. However, a major goal of our efforts is still the template construction of cyclic polycarbene ligands showing crown ether topology.

Research dealing with coordination chemistry encompasses the synthesis of tetradentate ligands with tripodal topology bearing different sets of amines, thiolates and hydroxides with varied arm length and poly(dithiolate) ligands formed by linkage of 1,2-benzenedithiol derivatives. The comprehensive investigation of their transition metal complexes are intended to deduce structure behavior relationships which we hope will shed light on the operation of active centers of certain metalloenzymes. Complexes of technetium, rhenium and gadolinium are being studied because of their medical-diagnostic relevance.