Study On The Synthesis, Characterization And Structure Of 1,2,4-diazaphospholes Ligands And Their Cu~Ⅱ,Fe~ⅡCoordination Compounds

The interest in five membered heterocyclic complexes has beenextensively explored due to their novel structural features andreactivity, and they had been widely used in the fields of organicreagent synthesis, new molecular materials, catalysis andanti-cancer drugs. With the development of 1,2,4-diazaphospholescompounds, the exploration on the synthesis method, structuralfeatures and coordinated modes of 1,2,4-diazaphospholes ligandsand their coordinated complexes have become critical in the fieldsof heterocyclic research.This research report mainly contained two parts: （1） A series ofplane unsymmetrically 1H-3,5-unsymmetrically-disubstituted-1,2,-4-diazaphospholes compounds were designed and synthesized, andthe synthesis and structural of these compounds were explored. （2）Based on 3,5-symmetracally-disubstituted-1,2,4-diazaphospholesligands, a series of 2,6-bis（3,5-disubstituted-1,2,4-diazaphosphol-1-yl）pyridine tridentate ligands had been synthesized, and thestructures and coordination mode of these ligands with Cu^Ⅱ, Fe^Ⅱtransition metal complexes had been explored. Details are asfollows:（a） The method of the general synthesis of 3,5-unsymmetrically disubstituted 1,2,4-diazaphospholes ligands had been improved.These mixed-substituted ligands were obtained by three stepswhich were started from the different N, N-dimethylalkylamide andusing no phosphaalkynes or phosphaalkenes. Also, the diversity of3,5-substituted groups were increased. With the improved method,six 3,5-unsymmetrically disubstituted-1H-1,2,4-diazaphospholesligands were synthesized. The structure of the compounds werecharacterized by¹H NMR,¹³C NMR,³¹P NMR and single-crystal X-raydiffraction analysis. X-Ray crystallography revealed that 3,5-unsymmetrically disubstituted-1,2,4-diazaphospholes ligandsstructures were linked by intermolecular disorder hydrogenbonds（N1-H…N）.（b） Three 2,6–bis（3,5-substituents-1,2,4-diazaphospholes-1-yl）-pyridine with CuII, FeIIcompounds were synthesized. 2,6–bis（3,5-substituents-1,2,4-diazaphospholes-1-yl）pyridine compounds weresynthesized with 3,5-symmetrical disubstituted-1H-1,2,4-diazaphospholes and 2,6-dibromopyridine. Corresponding three of metalcomplexes with CuII, FeIIwere obtained. The structure andcoordination mode of the compounds were investigatedsystematically by¹H NMR,³¹P NMR and X-ray single-crystal X-raydiffraction analysis. The results of X-Ray crystallography suggestedthat structures were linked by weak interaction of atoms andatomic force and hydrogen bonds.