Synthesis, molecular structure, conformational analysis, and chemical properties of silicon-containing derivatives of quinolizidine.
A silicon analog of quinolizidine 3,3,7,7-tetramethylhexahydro-1H-[1,4,2]oxazasilino[4,5-d][1,4,2]oxazasilin-9a-yl)methanol 3 was synthesized. X-ray diffraction analysis confirmed the trans configuration and low temperature NMR spectroscopy both the flexibility (barrier of interconversion 5.8 kcal mol(-1)) and the conformational equilibrium (chair-chair and chair-twist conformers) of the compound. The relative stability of the different isomers/conformers of 3 was calculated also at the MP2/6-311G(d,p) level of theory. Intra- and intermolecular hydrogen bonding in 3 and the appropriate equilibrium between free and self-associated molecules was studied in solvents of different polarity. Both the N-methyl quaternary ammonium salt and the O-trimethylsilyl derivative of 3 could be obtained and their structure determined.
A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Division of the Russian Academy of Science, 1 Favorsky Street, 664033, Irkutsk, Russian Federation. nataly_lazareva@irioch.irk.ru
Nataliya F
NF
Lazareva
Bagrat A
BA
Shainyan
Uwe
U
Schilde
Nina N
NN
Chipanina
Larisa P
LP
Oznobikhina
Alexander I
AI
Albanov
Erich
E
Kleinpeter
D018360:Crystallography, X-Ray; D008958:Models, Molecular; D015394:Molecular Structure; D054837:Quinolizidines / Q000138:chemical synthesis* / Q000737:chemistry; D012825:Silicon / Q000737:chemistry*
D054837:Quinolizidines; D012825:Silicon