Premium
Cationic Main Group Element Cages of Germanium(II) and Tin(II) Consisting of 3,5‐Di( t ‐butyl) Substituted Pyrazolyl Ligands in the Bridging Position
Author(s) -
Krummenacher Ivo,
Oschwald Claudia,
Rüegger Heinz,
Breher Frank
Publication year - 2007
Publication title -
zeitschrift für anorganische und allgemeine chemie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.354
H-Index - 66
eISSN - 1521-3749
pISSN - 0044-2313
DOI - 10.1002/zaac.200700237
Subject(s) - homoleptic , cationic polymerization , chemistry , tin , stereochemistry , trifluoromethanesulfonate , medicinal chemistry , steric effects , germanium , intramolecular force , crystallography , metal , polymer chemistry , catalysis , organic chemistry , silicon
The transamination reaction of [Ge{N(SiMe 3 ) 2 } 2 ] with two equivalents of 3,5‐di( t ‐butyl)pyrazole H(3,5‐ t Bu 2 pz) yielded the homoleptic germanium(II) pyrazolyl compound 4 . Treatment of 4 and its analogous tin(II) compound 1 with triflic acid (HOTf) in diethyl ether afforded cationic, triply pz‐bridged cages of the general formula [E( μ 2 ‐3,5‐ t Bu 2 pz) 3 E] + OTf − (E = Ge 5 , Sn 6 ) in good yields. The sterically demanding t ‐butyl substituted μ 2 ‐pyrazolyl bridges adopt a skew arrangement with respect to the E···E vector in the solid state. DFT calculations were performed on the cage compounds 5 and 6 in order to elucidate the influence of the tilting of the pyrazolyl ligands as well as a weak coordination of the triflate counter anion in 6 on the intramolecular element element distances within the cationic moieties.