Isomerism in the Chemistry of Organogermanium Compounds (Part II)

Abstract

The organogermanium chemistry covers huge fields, as shown by a survey covering the crystallographic and structural data of over four hundred and fifty examples. Over 10 percent of those compounds exist as distortion isomers (around 97 %) and ligand isomers (around 3 %). These are discussed in term of coordination around the Ge(II), Ge(IV) and Ge 2 +3 atoms, and correlations are drawn between donor atoms, bond lengths and bond angles. Distortion isomers differ by degree of distortion in GeL distances and L-GeL angles. Interestingly, in the chemistry germanium coordination complexes besides configuration isomers, also distortion isomers dominate.

Isomers in the Chemistry of Germanium Heterometallic Clusters

“…Yellow Cl 3 GeAu(PPh 3 ) 3 [5] exists in two isomeric forms, both are monoclinic. In each of the derivative two non equivalent moieties, Cl 3 Ge and Au(PPh 3 ) 3 are held together by a direct Ge -Au bond with the distances of 2.563(1) and 2.536(1) Å, respectively.…”

“…In each of the derivative two non equivalent moieties, Cl 3 Ge and Au(PPh 3 ) 3 are held together by a direct Ge -Au bond with the distances of 2.563(1) and 2.536(1) Å, respectively. Each M atom is a tetrahedrally coordinated (GeCl 3 Au and AuP 3 Ge).…”

“…In GeCu dimer [6], which contains two crystallographically independent dimers, two non equivalent units (C 6 F 5 ) 3 Ge and Cu(PPh 3 ) 2 are also held together by a direct Ge -Cu bond with the lengths of 2.370(2) and 2.382(3) Å, respectively. While each Ge atom is tetrahedrally coordinated (GeC 3 Cu) the Cu atoms have a trigonal planar environment (CuP 2 Ge) the mean Ge -C bond distances are 2.015 and 2.008 Å, respectively.…”

“…Another two dimers, GeMn [7] and GeSn [8] which also contain two crystallographically independent dimers, two non-equivalent units, (Ph) 3 Ge and Mn(CO) 5 [7] and (Me) 3 Ge and Sn(Ph 3 ) 3 [8], are connected also by a direct Ge -M bonds, 2.53(2) and 2.54(2) Å (M = Mn) and 2.596(4) and 2.567(6) Å (M = Sn). These are also classical examples of distortion isomerism ( Table 1).…”

“…In [2] we analysed and classified over twenty isomers in the chemistry of germanium coordination compounds. Another almost fifty isomeric examples in the chemistry of organogermanium compounds were also characterised and classified [3]. In this review we analyse and classify isomeric examples of germanium heterometallic derivatives to show a comprehensive view on the isomers in the chemistry of germanium.…”