36377-33-0Relevant articles and documents
Chirality-controlled syntheses of double-helical Au nanowires
Nakagawa, Makoto,Kawai, Takeshi
supporting information, p. 4991 - 4994 (2018/04/24)
The selective large-scale syntheses of noble metal nanocrystals with complex shapes using wet-chemical approaches remain exciting challenges. Here we report the chirality-controllable syntheses of double-helical Au nanowires (NWs) using chiral soft-templates composed of two organogelators with their own active functions; one organogelator serves to introduce helicity into the template and the other acts as a capping agent to control the Au shape. One-dimensional twisted-nanoribbon templates are prepared simply by mixing the two organogelators in water containing a small amount of toluene, followed by the addition of LiCl; template chirality is controlled through the selection of the handedness of the helicity-inducing organogelator. Double-helical Au NWs synthesized on these chiral templates have the same helical structure as the template because the Au NWs grow along both edges of the twisted nanoribbons with right- or left-handed helicities. Dispersions of the right- and left-handed double-helical Au NWs exhibit opposite CD signals.
Electroorganic synthesis 65. Anodic homocoupling of carboxylic acids derived from fatty acids
Weiper-Idelmann, Andreas,Aus Dem Kahmen, Martin,Schaefer, Hans J.,Gockeln, Marianne
, p. 672 - 682 (2007/10/03)
Fatty acid derived carboxylic acids with double bonds, hydroxy-, amino-, keto-, ester- and epoxy groups are anodically coupled to dimers (Kolbe electrolysis) in 29 to 81% yield and up to a 2.5 mol scale. Problems due to the low conductivity of fatty acid salts were overcome by the use of a flow cell with a narrow electrode gap. Fatty acids with branched alkyl chains gave dimers with interesting emulsifying properties. Dimethyl hexadecanedioate, accessible from methyl azelate, could be cyclized and further converted into homomuscone and muscone in a few steps. A commercial mixture of dimeric fatty acids (C36-dicarboxylic acids) has been coupled to give C70-diesters. Acta Chemica Scandinavica 1998. Part 64: Nielsen, M. F., Batanero, B.,.
An Asymmetric Synthesis of Acyclic and Macrocyclic α-Alkyl Ketones. The Role of (E)- and (Z)-Lithioenamines
Meyers, A. I.,Williams, Donald R.,White, Steven,Erickson, Gary W.
, p. 3088 - 3093 (2007/10/02)
Metalation and alkylation of chiral imines derived from C10, C12, and C15 cyclic ketones gave, under kinetic metalation conditions, 2-alkylcycloalkanones of absolute configuration opposite to that formed from thermodynamic metalation.Thus, (S)-(-)-2-methylcyclododecanone is formed kinetically in 60percent ee, whereas (R)-(+)-methylcyclododecanone is reached in 80percent ee under thermodynamic conditions.In a similar fashion, acyclic ketones 20, via their chiral imines 17, are alkylated enantioselectively under both kinetic and thermodynamic modes.The kinetic metalation gives exclusively the (Z)-lithioenamines (19), while reflux of this lithio anion gives only the (E)-lithioenamine (19).Chiral α-substituted ketones are produced in 18-97percent ee.
