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Periodic structures are often found in various areas of nanoscience and nanotechnology with many of them being used for metrological purposes either to calibrate instruments, or forming the basis of measuring devices such as encoders. Evaluating the period of one or two-dimensional periodic structures from topography measurements, e.g. performed using scanning probe microscopy (SPM) methods, can be achieved using different methodologies with many grating evaluation methods having been proposed in the past and applied to a handful of examples. The optimum methodology for determining the grating pitch is not immediately obvious. This paper reports the results of extensive large-scale simulations and analysis to evaluate the performance of both direct and Fourier space data processing methods. Many thousands of simulations have been performed on a variety of different gratings under different measurement conditions and including the simulation of defects encountered in real life situations. The paper concludes with a summary of the merits and disadvantages of the methods together with practical recommendations for the measurements of periodic structures and for developing algorithms for processing them., Comment: 34 pages, 11 figures, to be submitted to Measurement Science and Technology

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l0 5. Conclusion 1) The first and practical catalýic method for smooth deallylation of 2-substituted-2-allylmalonates to 2-substituted malonates via selective cleavage of the C-C bond under mild reaction conditions has been developed' The reaction seems to be general with respect to the transition-metal complexes; however, the comparison of Ru and Ni catalysts indicates considerable differences in their specific activity and selectiviý. Last but not least, the smooth deallylation offers an opportuniý to use the allyl group as an effective protective group for acidic hydrogen of malonic esters. 2) It has been shown that it is possible to re-route the course of the reaction from c{ bond cleavage (deallylation) to c{ bond formation (cyclization) in Ni hydride cataryzed, reactions by a change in the amount of organoaluminium. It proceeded in high yields even in cases where deallylation could compete with cyclization (e.g. diallylmalonate, etc.) in high selectiviý. In addition, generation of Ni hydride species in sinr provides an effective means for fast and selective cyclization of variously substituted 1,6- heptadienes to cyclopentanes. Moreover, it is possible exert certain level of control for the preferential formation of methylidene(methyl)cyclopentanes or cyclopentenes by the appropriate choice of thb...

This bachelor thesis is focused on the development of a new methodology leading to a novel type of N-heterocyclic [2,2]Paracyclophanes (we can also view these compounds as isoquinoline derivatives) based on directed C-H activation/annulation process. Within the thesis, necessary [2,2]Paracyclophane derivatives containing appropriate directing group and non-commercial alkynes have been prepared. Suitable catalytic conditions for the C-H activation/annulation reaction sequence have been found and subsequently optimized. Finally, to demonstrate the applicability of that method, several new N-heterocyclic [2,2]Paracyclophane derivatives have been prepared and characterized successfully. Key words: [2.2]Paracyclophane, C-H activation, annulation, Isoquinoline, directing group

The azafluoranthenes are a small group of natural substances, occuring in tropical vines from Menispermaceae family. They display promising medicinal effects (such as anti-HIV, cytotoxic activity) and other biological activities have been predicted. This bachelor thesis is focused on the synthesis of azafluoranthene core via directed C-H activation/annulation process. Firstly, required starting compounds have been prepared. In the next step, suitable catalytical conditions enabling the crucial transformation have been found and optimized. Finally, the applicability of the developed methodology has been confirmed by the synthesis of several new 1-azafluoranthene derivatives. Keywords: C-H activation, annulation, 1-azafluorathene, rhodium