Cyclophane Synthesis, Characterization And Quantum Chemical Calculations

Ferrocenophanes chemistry has continuously advanced and expanded over the years and has attracted the curiosity of organic chemists. Researchers of this field have designed and created new ferrocenophanes with a variety of structures. In these ferrocenophanes, many of the important properties of the parent ferrocene are retained, such as high electron density, aromaticity, thermal stability, favourable reaction activity and reversible redox characteristics. These ferrocenophanes are expected to show unique chemical properties owing to the functionality of the sidearm. Studies of these ligands are important because they have potential properties interesting for many research areas, such as redox or non linear optical properties, charge transport, liquid crystals, electrochemical recognition or catalysis. Therefore, the design and synthesis of ferrocenophanes attract great attention of synthesis chemists, and become a hot point in the field of organic synthesis.Six ferrocenophanes were designed synthesized in this paper. The ferrocenophanes were characterized by elemental analysis, IR, MALDI-TOF MS and ~1H NMR. Two crystal structures of them were determined by X-ray single crystal diffraction. According to the crystal structures, the quantum chemistry calculation was performed by Gaussian 03 program, and full geometry optimizations of two of the ferrocenophanes were carried out with DFT method at B3LYP/631G level. The structure, stability, net charge distribution and frontier molecular orbital components were discussed.[2, 2]paracyclophane show anomalous physical and chemical properties due to the transannularπ-electronic interaction between the stacked aromatic rings. [2, 2]paracyclophane (PCP) and its derivatives are commonly used as starting materials in the preparation of poly-p-xylylenes (parylene). Parylene is one kind of high performance coating materials. It has a great variety of excellent properties, such as electrical insulation, moisture resistance, mildew resistance, and noncorrosibility. Parylene is often used to provide conformal coatings on a variety of substrates, such as, for example, semiconductors, sensors, medical implant devices, cultural relic's and armament protection. Thus it is significant to study the synthesis of [2,2]paracyclophane.There are many references and patents which report the preparation of [2, 2] paracyclophane using 1, 6-Hofman elimination method. Various processes have been suggested for preparing [2, 2]-paracyclophane. Such known processes, however, are not fully satisfactory and are not suitable for industrial use. In this paper we study some reaction conditions on the basis of these reported references and patents, so as to achieve a considerable increase in yields and to provide pure [2, 2]paracyclophane with industrially acceptable yields.