The generation and reactivity of functionalised organozinc carbenoids for cyclopropane synthesis

This thesis describes the generation and reactivity of functionalised organozinc carbenoids for cyclopropane synthesis with alkenes. In the introductory chapter, a brief overview of the different methods for preparation of heteroatom-functionalised cyclopropanes is presented, including [2+1] cycloaddition reactions using a carbene or carbenoid as a cyclopropanating agent with an alkene, ionic stepwise methods, and chemical modifications from existing cyclopropanes. The remainder of this chapter then focuses on previous work within our own group in this area. The second chapter presents the results obtained from different areas of research in the present study, the first of these being a deeper understanding and extension of the research work undertaken by my predecessor for the development of the cyclopropanation reaction using an “amidoorganozinc” carbenoid derived from N,N diethoxymethyloxazolidinones derivatives in the presence of a source of zinc and chlorotrimethylsilane. Thus, the chemoselectivity and stereoselectivtity of the reaction were fully studied, and a quadrant model was constructed to rationalise the stereochemistry of the products obtained. The second part of this section outlines the generation of new enantiopure organozinc carbenoids precursors derived from substituted chiral precursors followed by the synthesis of novel enantiopure highly functionalised N-cyclopropyl oxazolidinones. The intramolecular version of this cyclopropanation reaction was then successfully studied using diethoxylactam derivatives as organozinc carbenoid precursors. The methodology was then applied to the preparation of novel aminocyclopropyl functionalised compounds selected as interesting building blocks which can lead to the synthesis of natural and biologically active compounds. The fifth part of this chapter describes subsequent studies towards the design of new carbenoid precursors containing additional functional groups of interest. Finally, a brief study on the potential of an organozinc carbenoid to participate in a novel [2,3] sigmatropic rearrangement was investigated. The thesis concludes with a summary of the results obtained, a detailed description of the experimental procedures used and the characterization and analysis of the compounds prepared, together with a full bibliography

Application of Stochastic Optimal Control to Financial Market Debt Crises

This interdisciplinary paper explains how mathematical techniques of stochastic optimal control can be applied to the recent subprime mortgage crisis. Why did the financial markets fail to anticipate the recent debt crisis, despite the large literature in mathematical finance concerning optimal portfolio allocation and stopping rules? The uncertainty concerns the capital gain, the return on capital and the interest rate. An optimal debt ratio is derived where the drift is probabilistic but subject to economic constraints. The crises occurred because the market neglected to consider pertinent economic constraints in the dynamic stochastic optimization. The first constraint is that the firm should not be viewed in isolation. The optimizer should be the entire industry. The second economic constraint concerns the modeling of the drift of the price of the asset. The vulnerability of the borrowing firm to shocks from the capital gain, the return to capital or the interest rate, does not depend upon the actual debt/net worth per se. Instead it increases in proportion to the difference between the Actual and Optimal debt ratio, called the excess debt. A general measure of excess debt is derived and I show that it is an early warning signal of the recent crisis.stochastic optimal control, dynamic optimization, mortgage crisis, Ito equation, risk aversion, debt management, warning signals

Stochastic Optimal Control Modeling of Debt Crises

What is an optimal or a sustainable external debt - for a country, region or sector? How should one monitor and evaluate debt to preclude a crisis? We use stochastic optimal control/dynamic programming to derive an optimal debt. The deviation of the actual from the optimal will serve as a Warning Signal of a crisis. There is a correspondence between Hamilton-Jacobi-Bellman equation of Dynamic Programming and the static Mean-Variance (M-V) analysis in finance. A graphic analysis of M-V is helpful to explain the implications of DP. An explicit example is the US Agricultural debt crisis.stochastic optimal control, debt, international finance, US agricultural crisis, Mean-Variance analysis, Hamilton-Jacobi-Bellaman equation

Greenspan, Dodd-Frank and Stochastic Optimal Control

Finanzmarkt; Regulierung; Zentralbank; Kontrolltheorie; USA

Interpreting children's rights education: three perspectives and three roles for teachers

In this article I argue that the world-view adopted by Children’s Rights Education (CRE) advocates influences the form of education they present. In the first part of the article I discuss three perspectives: (1) the legalistic perspective, which sees CRE as a matter of technical implementation; (2) the reformist-hermeneutic perspective, which focuses on the interpretation and elaboration of core children’s rights texts; and (3) the radical view, which sees CRE as part of a broader political struggle for education. In the second part I consider the implications of each of these perspectives for teachers and argue that only the latter tradition positions teachers as agents of change, whilst the others reduce teacher agency. The article argues that the first two perspectives are unlikely to achieve radical change for children, and that CRE advocates must engage more overtly with the politically contested nature of education

England’s citizenship education experiment: active citizenship or service?

This chapter compares the English tradition of active citizenship education (embodied in the national curriculum for Citizenship) with the US tradition of service-learning. Following some initial observations about the different traditions in the two countries the chapter focuses on three significant issues which are common to both traditions: (a) the type of experience which educators should facilitate; (b) the relationship between that experience and citizenship education; and (c) the pedagogy of experiential learning. The concluding section makes some suggestions as to why, given there are such significant shared educational and political concerns, the English educational community have not connected more positively with the longer established tradition of service-learning

Sharing by Design: Data and Decentralized Commons

Ambitious international data-sharing initiatives have existed for years in fields such as genomics, earth science, and astronomy. But to realize the promise of large-scale sharing of scientific data, intellectual property (IP), data privacy, national security, and other legal and policy obstacles must be overcome. While these issues have attracted significant attention in the corporate world, they have been less appreciated in academic and governmental settings, where solving issues of legal interoperability among data pools in different jurisdictions has taken a back seat to addressing technical challenges. Yet failing to account for legal and policy issues at the outset of a large transborder data-sharing project can lead to undue resource expenditures and data-sharing structures that may offer fewer benefits than hoped. We propose a framework to help planners create data-sharing arrangements with a focus on critical early-stage design decisions including options for legal interoperability