Two modifications of a five-coordinate silicon complex.
TBPY-5-34-(Butane-1,4-diyl)(2-{[1-(2-oxidophenyl)ethylidene-kappaO]amino-kappaN}ethanolato-kappaO)silicon, C(14)H(19)NO(2)Si, crystallizes in two modifications. The monoclinic form, (IIm), was obtained by crystallization over a period of 2 d at room temperature; the orthorhombic form, (IIo), crystallized overnight at 248 K. The main difference between the two molecular structures involves the angles in the equatorial plane of the trigonal bipyramid around silicon. Form (IIm) has an O-Si-O angle of ca 121 degrees and O-Si-C angles of ca 121 and 116 degrees . In form (IIo), the corresponding angles are approximately 123, 124 and 111 degrees . There are also significant differences in the packing: (IIm) shows pi stacking, whereas (IIo) does not.
Böhme
Uwe
U
Institut für Anorganische Chemie, Technische Universität Bergakademie Freiberg, Leipziger Strasse 29, 09596 Freiberg, Germany. uwe.boehme@chemie.tu-freiberg.de
Foehn
Ines C
IC