1984-06-1Relevant articles and documents
Structural Studies of Donor-Free and Donor-Solvated Sodium Carboxylates
Gauld, Richard M.,McLellan, Ross,Kennedy, Alan R.,Carson, Freya J.,Barker, Jim,Reid, Jacqueline,O'Hara, Charles T.,Mulvey, Robert E.
, p. 1615 - 1622 (2021)
Focusing mainly on sodium 2-ethylhexanoate, this study reveals that the carboxylate exists as a dimer in MeOD solution as evidenced by Diffusion Ordered NMR SpectroscopY (DOSY). Two crystalline varieties with distinct polymeric structures have been synthesised and crystallographically characterised. A mixed 1,10-phenanthroline–water solvate [{(C5H10)(C2H5)COONa.(H2O)[1,10-phen]}2]∞ contains dimeric [Na(OH2)]2 subunits, which propagate through hydrogen bonds between O atoms of the carboxylate and OH water bonds. Adjacent polymeric chains interdigitate with each other through π?π interactions between 1,10-phen rings. Solvent-free sodium 2-ethylhexanoate has five-coordinate cations comprising one bidentate chelating and three monodentate carboxylate oxygen atoms. Here, the packing arrangement is different with the central hydrophilic (NaO2)∞ core surrounded by a wrapping of disordered alkyl groups. A similar polymeric structure is observed for the crystalline DMSO-solvated sodium valproate [{(C3H7)(C4H8)COONa.(DMSO)}]∞. This adopts a layered arrangement comprising alternating sodium carboxylate hydrophilic layers and hydrophobic organic bilayers.
TARGETED NANOPARTICLES OF WELL-DEFINED AND REPRODUCIBLE SIZES
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Page/Page column 51, (2021/02/12)
The invention relates to a nanoparticle preparation comprising nanoparticles of well-defined and reproducible sizes, that are substantially free of aggregate formation.
A green resolution-separation process for aliphatic secondary alcohols
Ren, Liwei,Xu, Tian,He, Ruoping,Jiang, Zhenhua,Zhou, Hua,Wei, Ping
, p. 249 - 253 (2013/05/09)
In order to obtain both enantiomers of aliphatic secondary alcohols via a greener method, the four-step resolution-separation process involving lipase-catalyzed enantioselective esterification and hydrolysis as well as two separation procedures both via heterogeneous azeotropic distillation was developed. (S)-2-Pentanol (ee = 98.6%), (R)-2-pentanol (ee >99%), (S)-2-octanol (ee = 98.2%), and (R)-2-octanol (ee = 98.5%) were all produced in high purity (>98%) and high yield (>90%). In addition to the two model substrates, this method could also be applied to the resolution of other aliphatic secondary alcohols.