3046-26-2Relevant academic research and scientific papers
Impact of aryloxy initiators on the living and immortal polymerization of lactide
Chile,Ebrahimi,Wong,Aluthge,Hatzikiriakos,Mehrkhodavandi
, p. 6723 - 6733 (2017)
This report describes two different methodologies for the synthesis of aryl end-functionalized poly(lactide)s (PLAs) catalyzed by indium complexes. In the first method, a series of para-functionalized phenoxy-bridged dinuclear indium complexes [(NNO)InCl]2(μ-Cl)(μ-OPhR) (R = OMe (1), Me (2), H (3), Br (4), NO2 (5)) were synthesized and fully characterized. The solution and solid state structures of these complexes reflect the electronic differences between these initiators. The polymerization rates correlate with the electron donating ability of the phenoxy initiators: the para-nitro substituted complex 5 is essentially inactive. However, the para-methoxy variant, while less active than the ethoxy-bridged complex [(NNO)InCl]2(μ-Cl)(μ-OEt) (A), shows sufficient activity. Alternatively, aryl-capped PLAs were synthesized via immortal polymerization of PLA with A in the presence of a range of arylated chain transfer agents. Certain aromatic diols shut down polymerization by chelating one indium centre to form a stable metal complex. Immortal ROP was successful when using phenol, and 1,5-naphthalenediol. These polymers were analysed and chain end fidelity was confirmed using 1H NMR spectroscopy, MALDI-TOF mass spectrometry, and UV-Vis spectroscopy. This study shed light on possible speciation when attempting to generate PLA-lignin copolymers.
REACTION OF DIARYL ETHERS WITH ALKALI-METAL NITRITES
Plakhtinskii, V. V.,Ustinov, V. A.,Ryabukhina, N. S.,Mironov, G. S.,Kaninskii, P. S.
, p. 507 - 509 (2007/10/02)
The nucleophilic substitution of the aryloxy group in diaryl ethers by the nitrite ion leads to the formation of the corresponding substituted phenolates.The reaction rate increases with increase in the electron-withdrawing characteristics of the substituents both in the ring in which substitution occurs and in the leaving aryloxy group.
