Premium
N , N , O Ligands Based on Triazoles and Transition Metal Complexes Thereof
Author(s) -
Hübner Eike,
Fischer Nina V.,
Heinemann Frank W.,
Mitra Utpal,
Dremov Viacheslav,
Müller Paul,
Burzlaff Nicolai
Publication year - 2010
Publication title -
european journal of inorganic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 1434-1948
DOI - 10.1002/ejic.201000391
Subject(s) - chemistry , ligand (biochemistry) , medicinal chemistry , deprotonation , methylene , acetic acid , stereochemistry , crystallography , inorganic chemistry , organic chemistry , ion , biochemistry , receptor
The reaction of 2 H ‐benzotriazole ( 1 ) with dichloroacetic acid leads to the symmetric bis(2 H ‐benzotriazol‐2‐yl)methane ( 2c ) in 40 % yield. Deprotonation of 2c at the bridging methylene group and subsequent carboxylation with CO 2 yielded the new tripodal N , N , O ligand bis(2 H ‐benzotriazol‐2‐yl)acetic acid Hbbta ( 3 ). The sterically less demanding sodium 3,3‐bis(1 H ‐1,2,4‐triazol‐1‐yl)propionate Na[btp] ( 5 ) was obtained by saponification of methyl 3,3‐bis(1 H ‐1,2,4‐triazol‐1‐yl)propionate ( 4 ). The heteroscorpionate ligand 3 was treated with [MnBr(CO) 5 ] and [RuCl 2 (PPh 3 ) 3 ] to form the manganese tricarbonyl complex [Mn(bbta)(CO) 3 ] ( 6 ) and the air stable ruthenium complex [Ru(bbta)Cl(PPh 3 ) 2 ] ( 7 ). DFT calculations and the IR spectra of the carbonyl complex 6 reveal ligand 3 to be a less electron‐donating ligand compared to the bis(1 H ‐pyrazol‐1‐yl)acetic acid Hbpza. In case of the 1 H ‐1,2,4‐triazole‐based ligand 5 formation of coordination polymers were observed as proven by the synthesis of [Zn(btp) 2 ] ∞ ( 8 ) and [Mn(btp) 2 ] ∞ ( 9 ). Polymer 8 crystallises in linear chains of zinc atoms bridged by two molecules of ligand 5 each. These polymer chains show an interesting π‐stacking interaction between uncoordinated triazole residues of the ligands. Deposition of the coordination polymer on highly ordered pyrolytic graphite (HOPG) was successful and was analysed by scanning tunnelling microscopy (STM). Reaction of Na[btp] ( 5 ) with MnSO 4 · H 2 O resulted in a metal organic framework (MOF) [Mn(btp) 2 ] ∞ ( 9 ).