10341-25-0Relevant articles and documents
Dynamic Rotational Motions of Vaulted Chiral trans-Bis(salicylaldiminato)palladium(II) Complexes Bearing Rigid or Flexible Carbon Chain Linkers
Ikeshita, Masahiro,Naota, Takeshi
, p. 4689 - 4695 (2018)
Planar chiral, trans-bis(salicylaldiminato)palladium(II) complexes having a macrocyclic vaulting structure consisting of either a heptamethylene-butadiynylene-heptamethylene (1) or polymethylene (2) bridge were synthesized and subsequently characterized by NMR, IR, high-resolution mass spectrometry, and single crystal XRD. The dynamic rotational behaviors of these vaulted complexes resulting from a skipping-rope-like molecular motion were examined on the basis of kinetic studies of the racemization of the optically pure (100 % ee) complexes. The chiral inversion rate was found to be significantly affected by the conformational flexibility of the complexes, which in turn could be controlled by adjusting the linker length, the linker rigidity, and the ligation properties of the solvent.
Structural Analysis and Inclusion Mechanism of Native and Permethylated α-Cyclodextrin-Based Rotaxanes Containing Alkylene Axles
Akae, Yosuke,Koyama, Yasuhito,Sogawa, Hiromitsu,Hayashi, Yoshihiro,Kawauchi, Susumu,Kuwata, Shigeki,Takata, Toshikazu
supporting information, p. 5335 - 5341 (2016/04/09)
Native α-cyclodextrin- (α-CD) and permethylated α-CD (PMeCD)-based rotaxanes with various short alkylene chains as axles can be synthesized through a urea end-capping method. Native α-CD tends to form [3]- or [5]pseudorotaxanes and not [2]- or [4]pseudorotaxanes, which indicates that the coupled CDs act as a single fragment. End-capping reactions of the pseudorotaxanes with C18 and C24 axle lengths do not occur because the axle termini are covered by the densely stacked CDs. The number of PMeCDs on the pseudorotaxane is flexible and mainly depends on the axle length. Peracetylated α-CD (PAcCD)-based rotaxanes are synthesized through O-acetylation of the α-CD-based rotaxanes without any decomposition of the rotaxanated structures. The structures of PMeCD-based [3]- and [4]rotaxanes, and the molecular dynamics calculations on [3]pseudorotaxanes, indicate that the tail face of PMeCDs is regularly directed toward the axle termini. On the basis of the results obtained, it can be concluded that the directions and numbers of CDs in rotaxanes containing short alkylene chains depend on 1)the interactions between CDs, 2)the length of the alkylene axle, and 3)the interactions between the axle end and tail face of the CD. Come on in! Native and permethylated α-cyclodextrin (CD)-based rotaxanes with various short alkylene axles are synthesized with a urea end-capping method. The directions and number of the CD wheels depend on the interactions between CDs, the axle length, and the interactions between axle ends and the tail face of the CDs (see figure).
Higher alcohols for solvents in amine production
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Page/Page column 2, (2008/06/13)
A nitrile-containing mixture, which includes a nitrile dissolved in a higher alcohol solvent, and hydrogen are fed to a reactor containing a catalyst. An amine is produced by hydrogenating the nitrile that is dissolved in the higher alcohol solvent. In a preferred embodiment, the reactor also contains a caustic solution. The preferred nitrile-containing mixture includes octadecaneditrile (ODDN) and hexanol to produce a preferred octadecanediamine (ODDA) through hydrogenation.
