TY  - JOUR
A1  - Mühleisen, M.
A1  - Tacke, Reinhold
T1  - Twofold deprotonated citric acid as a bidentate ligand of pentacoordinate silicon: synthesis and structural characterization of the zwitterionic \(\lambda_5\)Si-spirosilicate bis[citrato(2-)-O\(^3\),O\(^4\)][(dimethylammonio)methyl]silicate hydrate
N2  - The zwitterionic \(\lambda_5\) Si-spirosilicate bis[ citrato(2-)-0\(^3\) ,0\(^4\) )[ ( dimethylammonio) methyl]silicate (4) was synthesized by reaction of (MeO)\(_3\)SiCH\(_2\)NMe\(_2\) (3) with citric acid (molar ratio 1 :2) in acetonitrile at room temperature and isolated, after crystallization from water, as the hydrate 4 · H\(_2\)O (yield 81 %). The crystal structure of 4 · H\(_2\)O was studied by single-crystal X-ray diffraction. The alcoxide oxygen atoms and central carboxylate oxygen atoms of two citrato(2-) ligands and one carbon atom coordinate to the silicon atom of 4 · H\(_2\)O. The coordination polyhedron around the pentacoordinate silicon atom (SiO\(_4\)C framework) can be described as a distorted trigonal bipyramid, the two carboxylate oxygen atoms occupying the axial sites. The \(\lambda_5\) Si~silicon(IV) complex 4 also exists in solution (DMSO, H\(_2\)O).
KW  - Anorganische Chemie
KW  - Silicon
KW  - pentacoordinate
KW  - Lambda5Si-Spirosilicate
KW  - zwitterionic
KW  - Citrato(2-)-03
KW  - 04ligand
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64388
ER  - 
TY  - JOUR
A1  - Mühleisen, M.
A1  - Tacke, Reinhold
T1  - meso-[1,4-Piperaziniumdiylbis(methylene)]bis{bis[2-methyllactato(2-)-O1,O2]silicate} octahydrate: synthesis and crystal structure analysis of a zwitterionic dispirocyclic \(\lambda^5\)Si,\(\lambda^5\)Si'-disilicate
N2  - The zwitterionic dispirocyclic \(\lambda^5\)Si,\(\lambda^5\)Si'-disilicate meso-[1 ,4-piperaziniumdiylbis( methylene)]bis{ bis[ 2-methyllactato(2-)-O\(^1\),O\(^2\)]silicate} octahydrate (6-8H\(_2\)O) was synthesized by reaction of 1,4-bis[(trimethoxysilyl}methyl] piperazine (8) with 2-methyllactic acid (molar ratio 1:4) in water/acetone (yield 82%). The molecular dinuclear silicon(IV) complex 6 contains two pentacoordinate (formally negatively charged) silicon atoms and two tetracoordinate (formally positively charged) nitrogen atoms. The crystal structure of 6•8H20 was studied by X-ray diffraction.
KW  - Anorganische Chemie
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64396
ER  - 
TY  - JOUR
A1  - Tacke, Reinhold
A1  - Mühleisen, M.
T1  - Bis[benzilato(2-)-O\(^1\),O\(^2\)][2-(dimethylammonio)ethoxy]silicate: synthesis and structural characterization of a zwitterionic \(\lambda^5\)Si-silicate with a SiO\(_5\) framework
N2  - No abstract available
KW  - Anorganische Chemie
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64400
ER  - 
TY  - JOUR
A1  - Tacke, Reinhold
A1  - Mühleisen, M.
A1  - Jones, P. G.
T1  - Das erste zwitterionische, optisch aktive Disilicat mit pentakoordiniertem Silicium
N2  - No abstract available
KW  - Anorganische Chemie
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64343
ER  - 
TY  - JOUR
A1  - Tacke, Reinhold
A1  - Mühleisen, M.
A1  - Jones, P. G.
T1  - The first zwitterionic, optically active disilicate with pentacoordinate silicon
N2  - No abstract available
KW  - Anorganische Chemie
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64358
ER  - 
TY  - JOUR
A1  - Tacke, Reinhold
A1  - Mühleisen, M.
T1  - Hexakoordiniertes Silicium in einer molekularen Verbindung mit einer F\(_5\)SiC-Einheit
N2  - No abstract available
KW  - Anorganische Chemie
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64365
ER  - 
TY  - JOUR
A1  - Tacke, Reinhold
A1  - Mühleisen, M.
T1  - Hexacoordinate silicon in a compound with an F\(_5\)SiC unit
N2  - No abstract available
KW  - Anorganische Chemie
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64378
ER  -