@article{TackeWagnerBrakmannetal.1993,
  author    = {Tacke, Reinhold and Wagner, S. A. and Brakmann, S. and Wuttke, F. and Eilert, U. and Fischer, L. and Syldatk, C.},
  title     = {Synthesis of acetyldimethyl(phenyl)silane and its enantioselective conversion into (R)-(1-hydroxyethyl)dimethyl(phenyl)silane by plant cell suspension culytures of Symphytum officinale L. and Ruta graveolens L.},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64299},
  year      = {1993},
  abstract  = {Starting from chlorodimethyl(phenyl)silane (3), acetyldimethyl(phenyl)silane (l) was prepared by a two-step synthesis in a total yield of 90\% [PhMe\(_2\)SiCl (3)-> PhMe\(_2\)SiCCOMe)=CH\(_2\) (4)-> PhMe\(_2\)SiC(O)Me (1)]. The prochiral acetylsilane 1 was transfonned enantioselectively into (R)-(1-hydroxyethyl)dimethyl(phenyl)silane [(R)-2] using plant cell Suspension cultures of Symphytum officinale L. or Ruta graveolens L. Under preparative conditions (300-mg scale, not optimized), (R)-2 was isolated in 15\% (Symphytum) and 9\% yield (Ruta), respectively. The enantiomeric purities of the products were 81\% ee (Syrnphytum) and 60\% ee (Ruta), respectively.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeBrakmannWuttkeetal.1991,
  author    = {Tacke, Reinhold and Brakmann, S. and Wuttke, F. and Fooladi, J. and Syldatk, C. and Schomburg, D.},
  title     = {Stereoselective microbial reduction of racemic acetyl(t-butyl)methylphenylsilane by Trigonopsis variabilis (DSM 70714) and Corynebacterium dioxydans (ATCC 21766)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64109},
  year      = {1991},
  abstract  = {(SiR,CR)- and (SiS,CR)-t-butyl(l-hydroxyethyl)methylphenylsilane [(SiR,CR)-2 and (SiS,CR)-3] have been prepared by (R)-selective microbial rcduction of racemic acetyl(t-butyl)methylphenylsilane (rac-1) using resting free cells of the yeast Trigonopsis variabilis (DSM 70714) or the bacterium Corynebacterium dioxydans (ATCC 21766). The biotransfonnations were carried out on a 10 g scale. Afterseparation by column chromatography on silica gel, the optically active diastereomers (SiR,CR)-2 and (SiS,CR)-3 produccd by T. variabilis were obtained in good yields [74\% ((SiR,CR)-2). 78\% ((SiS,CR)-3)]. The products obtained from the reduction with C. dioxydans were isolated in significantly lower yields [20\% ((SiR,CR)-2), 20\% ((SiS,CR)-3)]; reaction conditions not optimized). Both bioconversions gave products with high enantiomeric purities (T. variabilis: 91\% ee ((SiR,CR)-2), 96\% ee ((SiS,CR)-3); C. dioxydons: ~ 991 ee ((SiR,CR)-l), ~ 99\% ee ((SiS,CR)-3)). To throw light on the stereochemical aspects of these biotransfonnations, an X-ray diffraction study was carried out on the 3,5-dinitrobenzoate of rac-(SiR,CS/SiS,CR)-3. In addition, 1H NMR spectroscopic stereochemical correlation studies were performed with the (S)-MTPA esters derived from (SiR,CR)-l, (SiS,CR)-3, rac-(SiR,CRjSiS,CS)-2 and rac-(SiR,CSjSiS,CR)-3 [rac-(SiR,CR/ SiS,CS)-2 and rac-(SiR,CS/SiS,CR)-3 were obtained by reduction of rac-1 with LiAIH\(_4\) in diethylether, followed by chromatographic separation of the diastereomers on silica gel]. These stereochemical studies allowed assignment of the absolute configurations and enantiomeric purities of the biotransformation products.},
  subject      = {Anorganische Chemie},
  language  = {en}
}