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archives@tulane.edu / Abstract Condensation of 1,8,13-tris(mercaptomethyl)triptycene and tris(bromomethyl)methane yields the in,in-cyclophane 30 in 8% yield with two inwardly directed methine groups. The X-ray analysis clearly shows that it is the in,in-isomer. The proton NMR spectrum displays an obvious coupling between the two methine hydrogens, which was proved by selectively irradiation one of the apical methine proton. The coupling constant is 2.0 Hz, which is the largest through-space coupling observed so far. Based on DFT and MP2 calculations, the hydrogen-hydrogen non-bonded contact distance is estimated to be 1.50-1.53 Å. Two in,in-cyclophanes 31 and 56, containing one or two methyl groups in their central cavities, have been synthesized, crystallized and fully characterized by ¹H and ¹³C NMR spectroscopy, MALDI-TOF mass spectrometry, IR spectroscopy, and X-ray crystallography. Cyclophane 31 is the first example of an in,in-cyclophane with a methyl group inside the cavity. The IR spectrum clearly shows that the Si-H stretch is blue-shifted from 2177 cm-1 in an acyclic model to 2269 cm-1. Based on computational studies, cyclophane 31 has a very short non-bonded H---CH3 distance of about 2.30 Å. Cyclophane 56 does not have short non-bonded contact distance, but it is the first example of a macrobicyclic compound that contains two inwardly directed methyl groups. Three cyclophanes with the formula (C28H31PS3)n, where n = 1 or 2, were isolated from the base-promoted macrocyclization of tris(2-mercaptophenyl)phosphine and tris(3-bromopropyl)methane. Spectroscopic and X-ray analysis showed them to be the in,in-isomer 32, the in,out-isomer 60, and a dimeric in,out,in,out-isomer 61. Compounds 32 and 61 display approximately C3-symmetric and Ci-symmetric structures, respectively, in the crystal, but compound 60 adopts two distinct low-symmetry conformations in the solid state. In each case, the observed structures correspond to the lowest energy conformations of their respective isomers as calculated at the B3PW91/6-31G(d) level of theory. The in,in-isomer 32 displays a close contact between the phosphine in-lone pair and the in-methine group, with through-space spin-spin coupling constants of JPH = 9 Hz and JPC = 24 Hz, the latter of which appears to be the largest reported phosphorus-carbon through-space coupling constant. Dodecaphenyltetracene (75), the largest perphenylacene yet prepared, was synthesized from known tetraphenylfuran, hexaphenylisobenzofuran, and 1,2,4,5-tetrabromo-3,6-diphenylbenzene in three steps. The X-ray structure of the deep red, highly luminescent 75 shows it to be a D2-symmetric molecule with an end-to-end twist of 97o. The central acene is encapsulated by the peripheral phenyl substituents, and as a result, the molecule is relatively unreactive and even displays reversible electrochemical oxidation and reduction. Decaphenylphenanthrene (77), the first nonlinear perphenyl polycyclic aromatic hydrocarbon to be prepared so far, has been made from tetraphenylfuran and 1,2,3,4-tetrabromo-5,6-diphenylbenzene in two steps. The X-ray structure contains two independent molecules of 77, and each of them ppssesses approximate C2 symmetry in the crystal. / 1 / yonglong xiao

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The infrared spectra of mixtures of HC1 and the following have been recorded in the gas phase and low temperature matrices: argon, ethene, ethyne, de-benzene, fluorobenzene, CO, CO 2 , SOz, CC1*, CHCls, de-acetone, ethanal, HCN and acrylonitrile. The features which have been measured are: firstly the changes in the integrated intensity of lines in the rotation-vibration spectrum of the fundamental HC1 band as a function of interactions with other components of the mixture, and secondly bands associated with specific interactions forming hydrogen-bonded complexes. The enhancement of HC1 is generally found to vary linearly with the pressure of added gas over a limited pressure range. Assuming that line enhancement is caused by collisionally-induced rotation-translation energy exchange to or from the HC1 molecule, a combination of expressions derived from Ehrenfest's Adiabatic Principle and the "rigid rotor" approximation leads to a model which qualitatively predicts the enhancements observed. The model also rationalises the enhancement of HCN and SOa absorptions by HC1. Examination of the experimentally determined data leads to the conclusion that the total intermolecular force between the monomer base and HC1 controls the degree of enhancement but it is concluded that there is no general connection between the degree of HC1 enhancement and hydrogen-bond strength. Hydrogen-bonded complexes were examined in the gas and argon matrix phases and the shifts in the modified hydrogen chloride stretch compared for various bases. The spectra of pi-complexes formed between HC1 and ethene, ethyne and benzene were found to be detectable by low-resolution infrared spectroscopy at room temperature. Complexation of HCN, he-acetone and de-acetone with HC1 caused CN and C=O band shifts. The Chem-X molecular modelling program was evaluated by using it to predict the geometry of simple complexes for which experimental data is already available. It is concluded that the program requires more development before it can be confidently used as a theoretical aid with which to study hydrogen-bonded dimers.

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Tariff is a taxation that a government collects on inbound or outbound goods. The Customs, which is the institution performing this function, plays a major role in national financial and economic development. In the world every country has struggled to reduce production cost by marketing economic and trade with foreign countries as well as increasing their competitive ability. Accordingly, bonded system is designed for deferring tariff payment and reliving production burden. Almost every country enacted bonded laws as legal basis to regulate bonded systems. The so-called ¡§bonded cargo¡¨ refers to the cargo which deposit, assemble, arrange, divide up, sort inside bonded area under the monitor by the Customs and is allowed to defer tariff payment. The Customs effectively monitor and control bonded cargo and bonded regions according to customs laws. No matter industrialized countries, developing countries, or the third world countries, their Customs have endeavored to establish bonded system in accordance with their individual sources, economic and trade environments. Under the globalization trend they also establish transnational branches to cope with domestic demand. Furthermore, under the regulations by World trade Organizations or World Customs Organization, The Customs promptly review or revise their polices related to bonded regulations to expedite customs clearance complying with industrial demand. The concerned sphere includes such as bonded warehouse, factory, export processing zone, cross-strait bonder model, developing some specific targets into bonded regions. For example, science-based industrial or agriculture science park, bonded area(free trade zone) and free trade ports will be multiplatform areas in the future. Our bonded affairs also will be varied, complicated and more mature at the same time. This study found that the cross-strait parties enthusiastically push the modernization and globalization of bonded systems with the methods such as website application and clearance, accounting audit. While international economic condition changes swiftly, the industries eager for the Customs speeding up clearance service. Comparatively their bonded measures still can¡¦t meet their request and have some blind spots and bottlenecks. The customs should adopt more opening and automated management models, risk management, accounting theory, new technology etc. to simplify the control of bonded goods as well as shorten process of logistics control. The final goals are to shift their trend from ¡§monitor control ¡§to partnership and finally reach global alignment.

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