441799-30-0Relevant academic research and scientific papers
An enaminone-directed benzannulation/macrocyclization approach to cyclophane ring systems
Pigge, F. Christopher,Ghasedi, Fatemeh,Rath, Nigam P.
, p. 4547 - 4552 (2002)
A straightforward and modular preparative approach to 1,3,5-triaroylbenzene-based functionalized cyclophane ring systems has been developed. The key cyclophane-forming macrocyclization reaction was accomplished during the course of a regioselective cross-benzannulation between bis(aryl ethynyl) ketone and enaminone reactants. Macrocyclic products with ring sizes ranging from 18-to 22-membered were successfully constructed. The composition of the tether connecting the two aryl ethynyl ketone fragments can be easily varied; consequently, this method is suitable for construction of a diverse range of structurally distinct cyclophane products. To illustrate this feature, cyclophanes possessing xylyl, alkyl, di(ethylene triamine), and di(ethylene oxy) bridging units were synthesized in isolated yields of 11-46%. Three new cyclophanes (calixarene-like macrocyles 8 and 9, as well as crownophane 18) were structurally characterized by X-ray diffractometry.
Recyclable, Strong, and Highly Malleable Thermosets Based on Boroxine Networks
Ogden, William A.,Guan, Zhibin
supporting information, p. 6217 - 6220 (2018/05/23)
Traditional thermoset materials have favorable material properties but are unable to reprocess and are difficult to recycle. Small molecule boroxines have been shown to undergo a reversible exchange reaction. Herein we employ boroxine as dynamic cross-lin
Malleable and Self-Healing Covalent Polymer Networks through Tunable Dynamic Boronic Ester Bonds
Cromwell, Olivia R.,Chung, Jaeyoon,Guan, Zhibin
supporting information, p. 6492 - 6495 (2015/06/08)
Despite numerous strategies involving dynamic covalent bond exchange for dynamic and self-healing materials, it remains a challenge to be able to tune the malleability and self-healing properties of bulk materials through simple small molecule perturbations. Here we describe the use of tunable rates of boronic ester transesterification to tune the malleability and self-healing efficiencies of bulk materials. Specifically, we used two telechelic diboronic ester small molecules with variable transesterification kinetics to dynamically cross-link 1,2-diol-containing polymer backbones. The sample cross-linked with fast-exchanging diboronic ester showed enhanced malleability and accelerated healing compared to the slow-exchanging variant under the same conditions. Our report demonstrates the possibility of transferring small molecule kinetics to dynamic properties of bulk solid material and may serve as a guide for the rational design of tunable dynamic materials.
