Fully Aromatic High Performance Thermoset via Sydnone–Alkyne Cycloaddition
作者:Nisha V. Handa、Shaoguang Li、Jeffrey A. Gerbec、Naoko Sumitani、Craig J. Hawker、Daniel Klinger
DOI:10.1021/jacs.6b03381
日期:2016.5.25
on the 1,3-dipolar cycloaddition of a bifunctional sydnone with a trifunctional alkyne. These processable materials possess outstanding thermal stability, with Td5% of 520 °C and a weight loss of <0.1% per day at 225 °C (both in air). Key to this performance is the stability of the starting functional groups that allows for reactive B-staging via simple thermal activation to give fully aromatic and
我们开发了一种高效的合成平台,用于制备基于双官能 sydnone 与三官能炔烃的 1,3-偶极环加成反应的新型高性能热固性塑料。这些可加工材料具有出色的热稳定性,520 °C 下的 Td5% 和 225 °C 下每天的重量损失 <0.1%(均在空气中)。这种性能的关键是起始官能团的稳定性,它允许通过简单的热活化进行反应性 B 阶跃,以提供完全芳香族和高度交联的基于聚吡唑的热固性材料。
Yashunskii,V.G.; Kholodov,L.E., Journal of general chemistry of the USSR, 1962, vol. 32, p. 3592 - 3596
作者:Yashunskii,V.G.、Kholodov,L.E.
DOI:——
日期:——
Stille,J.K. et al., Journal of Heterocyclic Chemistry, 1966, vol. 3, p. 155 - 157
作者:Stille,J.K. et al.
DOI:——
日期:——
Bis- N -nitroso-caged nitric oxides: photochemistry and biological performance test by rat aorta vasorelaxation
Three new caged nitric oxides (NOs)-BNN3, BNN5Na, and BNN5M-were tested for biological use. BNNs have a strong ultraviolet (UV) absorption band (lambda(max): 300 nm, epsilon: 13.5 mM(-1) cm(-1)) extended to 420 nm and produce NO upon irradiation with 300-360 nm light in quantum yields about 2. A photoexcited BNN molecule yields two NOs with time constants of less than 10 ns for phase 1 and less than 20 mu s for phase 2 at 37 degrees C, suggesting usefulness of BNNs for measuring in vivo and in vitro fast NO reactions. Upon irradiating with UV light, caged nitric oxides-loaded rat aortic strips maintained in a state of active tonic contraction effectively relaxed (<3 mu M BNN5M loading solution concentration). BNN3 is incorporated in the lipid membrane. BNN5Na, insoluble in organic solvents but water soluble, localizes in the water phase. BNN5M, is muscle-cell-permeable and hydrolysed to BNN5Na to remain in cytosol. BNNs were thermally stable and demonstrated no observable toxicity. (C) 1999 Elsevier Science Ltd. All rights reserved.