Chemical specific cycloaddition of diethanolamine to germanium dioxide

Article abstract of DOI:10.1016/0277-5387(94)00287-O

A specific cycloaddition of various diethanol amines to germanium dioxide is described. The N-alkyl and N-H diethanolamines give the trimeric cyclotrigermoxane, 1, and monomeric spiro-germocane, 2, respectively. An equilibrium between 1, 2 and their precursor, the geminal dihydroxygermocane, 3, is observed. Complex 3 can be trapped by using α-hydroxydiphenylacetic acid to give a stable spiro-germocane, (α-hydroxydiphenylaceto-O,O')(iminodiethanolato-N,O,O')germanium(IV) (4) in high yield. These complexes have been characterized by elementary analysis, IR, (1)H and (13)C NMR and mass spectra.