121263-90-9Relevant articles and documents
Design of Aminopolymer Structure to Enhance Performance and Stability of CO2 Sorbents: Poly(propylenimine) vs Poly(ethylenimine)
Pang, Simon H.,Lee, Li-Chen,Sakwa-Novak, Miles A.,Lively, Ryan P.,Jones, Christopher W.
, p. 3627 - 3630 (2017)
Studies on aminopolymer/oxide composite materials for direct CO2 capture from air have often focused on the prototypical poly(ethylenimine) (PEI) as the aminopolymer. However, it is known that PEI will oxidatively degrade at elevated temperatur
Parameters influencing the release of tertiary alcohols from the surface of "spherical" dendrimers and "linear" stylomers by neighbouring-group-assisted hydrolysis of 2-carbamoylbenzoates
Trachsel, Alain,De Saint Laumer, Jean-Yves,Haefliger, Olivier P.,Herrmann, Andreas
supporting information; experimental part, p. 2846 - 2860 (2009/12/04)
The influence of structural and physico-chemical parameters on the release of a volatile tertiary alcohol (2-methyl-l -phenyl-2-propanol) by neighbouring-group-assisted cyclisation of 2-carbamoylbenzoates at neutral pH was investigated by comparing the covalent-bond cleavage from the surface of linear, comblike poly(propylene imine) "stylomers" and their corresponding spherical, globular dendrimers. Determination of the kinetic rate constants for the stepwise intramolecular cyclisation of the 2-carbamoylben- zoate moiety by using HPLC showed that the polarity of the conjugates, and thus their solubility in the aqueous reaction medium, has a stronger influence on the rates of hydrolysis than the size (generation) or shape (linear or spherical) of the macromolecules. Furthermore, structural modifications in close proximity to the release unit, such as the presence of functionalities with catalytic activity, have a strong impact on the release efficiency of the active molecules. An understanding of the physico-chemical parameters determining the local environment of the covalent-bond cleavage site is therefore an important prerequisite to transfer the characteristics of small molecules to larger structures such as oligomers and polymers and thus to design efficient macromolecular conjugates for the controlled delivery of bioactive compounds.
Influence of the distance between ionizable groups on the protonation behavior of various hexaamines
Van Duijvenbode, Rene C.,Rajanayagam, Anton,Koper, Ger J.M.,Borkovec, Michal,Paulus, Wolfgang,Steuerle, Ulrich,Haeussling, Lukas
, p. 5649 - 5652 (2007/10/03)
A synthesis route for N,N,N',N'-tetraaminoethyl-1,2-ethylenediamine, N,N,N',N'-tetraaminopropyl-1,2-ethylenediamine, N,N,N',N'-tetraaminopropyl- 1,3-propylenediamine and N,N,N',N'-tetraaminopropyl-1,4-butylenediamine is presented. These molecules differ from each other in the number of carbon atoms between the six amino groups. This results in different protonation behavior. Potentiometric titrations are performed in 0.1 M and 1.0 M KCl, and the six macroscopic protonation constants are obtained from these curves. An Ising model with a limited number of microscopic protonation constants and short-ranged pair interactions describes the protonation behavior quantitatively. The results are compared to those of other, similar molecules. The advantage of the Ising model over empirical relations such as the Taft equations is the more systematic approach with which the titration curves of more complex molecules can be described. The values for the Ising model parameters obtained here can be used to predict the protonation behavior of more complex, in particular larger, polyamines.
