通过环丁结合的六-四-六enzocoronene 网络
Bryan K Spraul1, S Suresh, Sibylle Glaser
1Center for Optical Materials Science and Engineering Technologies (COMSET), Department of Chemistry and School of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA.
Journal of the American Chemical Society
|October 8, 2004
概括
研究人员合成了新型的三维尼尔以太替代的六环六enzocoronene (HBC) 并将其聚合成 perfluorocyclobutyl (PFCB) 聚合物. 这一突破提供了可加工的HBC光学材料,克服了以前的溶解性挑战.
科学领域:
- 有机化学 有机化学
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
背景情况:
- 六环六enzocoronene (HBC) 衍生品表现出可取的特性,如液晶性,孔运输和可调节的发射.
- 不溶性和难以附加聚合基的困难限制了HBC衍生物的实际应用.
- 现有的合成路径经常在反应条件下与功能组的稳定性作斗争.
研究的目的:
- 为了首次合成新型的三维尼尔以太替代的六环六enzocoronene (HBC).
- 将这些新型HBC衍生物聚合成完全环 (PFCB) 聚合物和共聚物.
- 通过克服可溶性限制,开发可加工的基于HBC的光学材料.
主要方法:
- 合成三维尼尔以太替代的HBC.
- 合成的HBC单体的聚合,使用完环 (PFCB) 化学.
- 由此产生的聚合物和共聚合物的表征.
主要成果:
- 成功合成三乙烯基乙烯替代HBC,在氧化条件下表现出稳定性,与碳化合物不同.
- 这些单体的聚合成PFCB聚合物和共聚物.
- 将离散的HBC单元纳入PFCB聚合物骨干中,从而产生潜在的可加工材料.
结论:
- 三乙烯替代剂与HBC化学相容,并使聚合成为可能.
- 含有HBC单元的 perfluorocyclobutyl (PFCB) 聚合物为可溶和可加工的基于HBC的光学材料提供了一条途径.
- 这项工作扩大了功能HBC材料的可访问性,用于先进的应用.
相关概念视频
Thermal Electrocyclic Reactions: Stereochemistry
The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Photochemical Electrocyclic Reactions: Stereochemistry
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.
Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
The Diels–Alder reaction is one of the robust methods for synthesizing unsaturated six-membered rings. The reaction involves a concerted cyclic movement of six π electrons: four π electrons from the diene and two π electrons from the dienophile.
Five-Membered Heterocyclic Aromatic Compounds: Overview
Heterocyclic aromatic compounds are cyclic compounds that are aromatic and have one or more heteroatoms—atoms other than carbon, in the ring. Depending upon the number of atoms present in the ring, they can be either five or six-membered. Examples of five-membered heterocyclic aromatic compounds include pyrrole, furan, thiophene, and imidazole. Pyrrole consists of one nitrogen atom having one lone pair of electrons. Furan and thiophene have one oxygen and one sulfur heteroatom, respectively.
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
Robinson annulation is a base-catalyzed reaction for the synthesis of 2-cyclohexenone derivatives from 1,3-dicarbonyl donors (such as cyclic diketones, β-ketoesters, or β-diketones) and α,β-unsaturated carbonyl acceptors. Named after Sir Robert Robinson, who discovered it, this reaction yields a six-membered ring with three new C–C bonds (two σ bonds and one π bond).


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