Synthesis, X-ray diffraction studies, and DFT calculations on hexacoordinated germanium derivatives: the case of germaspirobis(ocanes)

Sergey S Karlov; Elmira Kh Lermontova; Maxim V Zabalov; Anastasia A Selina; Andrei V Churakov; Judith A K Howard; Mikhail Yu Antipin; Galina S Zaitseva

doi:10.1021/ic048165m

Synthesis, X-ray diffraction studies, and DFT calculations on hexacoordinated germanium derivatives: the case of germaspirobis(ocanes)

Inorg Chem. 2005 Jun 27;44(13):4879-86. doi: 10.1021/ic048165m.

Authors

Sergey S Karlov¹, Elmira Kh Lermontova, Maxim V Zabalov, Anastasia A Selina, Andrei V Churakov, Judith A K Howard, Mikhail Yu Antipin, Galina S Zaitseva

Affiliation

¹ Chemistry Department, Moscow State University, B-234, Leninskie Gory, 119899 Moscow, Russia. sergej@org.chem.msu.su

PMID: 15962997
DOI: 10.1021/ic048165m

Abstract

Synthesis of the title compounds, viz. [RN(CH2CHR'O)2]2Ge (1, R = Me, R' = H; 2, R = Me, R' = Ph; 3, R = Ph, R' = H), by the reaction of 2 equiv of corresponding dialkanolamines RN(CH2CHR'OH)2 (4, R = Me, R' = H; 5, R = Me, R' = Ph; 6, R = Ph, R' = H) with (AlkO)4Ge is reported. Composition and structures of all novel compounds were established by 1H and 13C NMR spectroscopy and mass spectrometry as well as elemental analysis data. The single-crystal X-ray diffraction of 2 has clearly indicated the presence of two transannular interactions Ge<--N in the compound. N atoms are cis-orientated. The compound 3 possesses long Ge...N distances. The structural data obtained from geometry optimizations by DFT calculations on 1-3 reproduces experimental results. Both cis- and trans-isomers were studied, and cis-configuration was found to be more thermodynamically stable for all three compounds. The transition states for possible cis <--> trans rearrangement processes in 1-3 were calculated. The properties of the Ge-O and Ge<--N bonds in 1-3 were analyzed by the AIM approach. The interactions between the Ge atom and N atoms as well as O atoms possess predominantly ionic character.