Stereoselective Access to Z and E Macrocycles by Ruthenium-Catalyzed Z-Selective Ring-Closing Metathesis and Ethenolysis

The first report of Z-selective macrocyclizations using a ruthenium-based metathesis catalyst is described. The selectivity for Z macrocycles is consistently high for a diverse set of substrates with a variety of functional groups and ring sizes. The same catalyst was also employed for the Z-selective ethenolysis of a mixture of E and Z macrocycles, providing the pure E isomer. Notably, an ethylene pressure of only 1 atm was required. These methodologies were successfully applied to the construction of several olfactory macrocycles as well as the formal total synthesis of the cytotoxic alkaloid motuporamine C

Synthesis of Highly Cis, Syndiotactic Polymers via Ring-Opening Metathesis Polymerization Using Ruthenium Metathesis Catalysts

The first example of ruthenium-mediated ring-opening metathesis polymerization generating highly cis, highly tactic polymers is reported. While the cis content varied from 62 to >95% depending on the monomer structure, many of the polymers synthesized displayed high tacticity (>95%). Polymerization of an enantiomerically pure 2,3-dicarboalkoxynorbornadiene revealed a syndiotactic microstructure

Highly Active Ruthenium Metathesis Catalysts Exhibiting Unprecedented Activity and Z‑Selectivity

A novel chelated ruthenium-based metathesis catalyst bearing an N-2,6-diisopropylphenyl group is reported and displays near-perfect selectivity for the Z-olefin (>95%), as well as unparalleled TONs of up to 7400, in a variety of homodimerization and industrially relevant metathesis reactions. This derivative and other new catalytically active species were synthesized using an improved method employing sodium carboxylates to induce the salt metathesis and C–H activation of these chelated complexes. All of these new ruthenium-based catalysts are highly Z-selective in the homodimerization of terminal olefins

Pedagogy as “Cryptic Politics”: Benjamin, Nietzsche, and the End of Education

T. J. Clark has described Walter Benjamin’s Arcades Project as containing a politics that is “cryptic,” as if “being actively aired and developed elsewhere.” This article seeks to uncover this uncover the buried foundations of such a politics in Benjamin’s early writings on pedagogy and to identify their cryptic nature with his traumatic break from Gustav Wyneken and the tragic failures of the Youth movement. This involves, on the one hand, an inversion of his early Nietzschean influences into a political anti-Nietzscheanism, one that this article explores through the figures of freedom, character and happiness. On the other, it involves a re-evaluation of his early understanding of education, in terms of the solitude of the learner and the silence of the school, to one that emphasises the function of the teacher as the intergenerational mediator who makes teachings transmissible. Noting the generalization of this understanding of education as a technological mediation between collective humanity and nature, it concludes by returning to the specific question of Benjamin’s anti-Nietzschean politics of education

SYNTHESIS AND CHARACTERIZATION OF 2,6-DIISOPROPYLPHENOXY TETRAPYRAZINOPORPHYRAZINES AS POTENTIAL MOLECULAR QUBITS

This thesis reports the synthesis of metal-free and metal-containing phthalocyanine derivatives using methods typical for that class of functional dyes. A mixture of the target compounds prepared here, one paramagnetic and one diamagnetic tetrapyrazinoporphyrazine, will be tested for their potential use in spintronics – the application of spin-active species in molecular electronics. Phthalocyanines and their derivatives are well-known for their ease of preparation and tunability; they have been utilized as sensitizers for photodynamic therapy of cancer and solar cells, as well as in catalysis and chemical sensing. Tetrapyrazinoporphyrazine complexes are compared with the parent phthalocyanine as their chemistry is similar but electronically are distinct. All compounds synthesized were investigated spectroscopically (UV-Vis, magnetic circular dichroism), electrochemically, and computationally; all methods showed the expected results typical of tetrapyrazinoporphyrazines. The paramagnetic vanadyl complex was confirmed by EPR spectroscopy and elucidated by single crystal X-ray diffraction. The green-colored macrocycles are substituted on their periphery by 2,6-diisopropylphenoxy groups; this creates a large nanoporous crystal stabilized by hydrophobic interactions that is useful for spintronic investigations. Under certain solvent conditions, a red linear trimeric product was isolated, and its optical properties and partial characterization is reported as well

Towards a Critique of Educative Violence: Walter Benjamin and ‘Second Education’

Although modern systems of mass education are typically defined in their opposition to violence, it has been argued that it is only through an insistent and critical focus upon violence that radical thought can be sustained. This article seeks to take up this challenge in relation to Walter Benjamin’s lesser-known writings on education. Benjamin retained throughout his life a deep suspicion about academic institutions and about the pedagogic, social and economic violence implicated in the idea of cultural transmission. He nonetheless remained committed to the possibility of another kind of revolutionary potential inherent to true education and, when he comes to speak of this in his Critique of Violence, it is remarkable that he describes it as manifesting an educative violence. This article argues that Benjamin’s philosophy works toward a critique of educative violence that results in a distinction between a ‘first’ and ‘second’ kind of education and asks whether destruction might have a positive role to play within pedagogical theories in contrast to current valorisations of creativity and productivity

Essays on Charitable Organizations and Public Policy

The dissertation analyzes public policies of subsidization and regulation in three contexts. Chapter 1 develops a dynamic bunching empirical design and uses it to estimate the compliance cost that IRS reporting requirements impose on public charities. Chapter 2 estimates the effects of tax and enforcement provisions of the Tax Reform Act of 1969 on charitable foundations and their donors. Chapter 3 estimates the impact of Pell Grant aid on student attainment and borrowing

Understanding The Relationship Between Moral Reasoning And Liberalism-Conservatism

This thesis aims to clarify the nature of the relationship between moral reasoning, as per the neo-Kohlbergian DIT approach of Rest and his colleagues, and liberalism-conservatism. Moral reasoning and liberalism-conservatism are consistently found to be related but the resultant interpretation that liberals are more moral-cognitively advanced than conservatives has been challenged by Emler and his colleagues who argue that the DIT is liberally biased. Subsequent research on this issue has produced a methodological quagmire that this thesis aims to proceed beyond. The specific aim of this thesis is to test several different (or competing) hypotheses purporting to explain the relationship between Kohlbergian moral reasoning and liberalism-conservatism. These are (1) that liberals are more morally advanced than conservatives; (2) that "advanced moral reasoning" is merely social presentation; (3) that moral reasoning is separately constrained by moral development and conservatism; (4) that moral development and liberalism represent distinct paths to postconventional reasoning preference; (5) that moral reasoning differences between liberals and conservatives are broader than usually thought; (6) that the political content of moral issues affects moral reasoning differences between liberals and conservatives; and (7) that moral reasoning instruments have exaggerated moral reasoning differences between liberals and conservatives. Study 1 found that a non-ipsative, indirect moral reasoning measure was correlated with liberalism-conservatism thus disconfirming hypotheses 2 and 7. Additionally, hypothesis 5 was not supported by several DIT findings. Opposing hypotheses 2 and 6, Study 2 found that a conservative version of the DIT was correlated with liberalism-conservatism although a potential methodological issue arose. Study 3 developed an objective measure of moral comprehension, broader in scope than previous moral comprehension measures, which demonstrated acceptable reliability and validity. Employing this measure, Study 4 found that moral comprehension and liberalism were weakly correlated and that they independently predicted moral reasoning, although their interaction did not. Together, these findings provide some support to hypotheses 1 and 4 but not hypotheses 3 and 6. Overall these findings reveal that liberals appear more moral-cognitively advanced than conservatives but, compared to conservatives, liberals appear to indicate preference for advanced moral reasoning earlier in their moral-cognitive development. This latter mechanism appears stronger and suggests that, although DIT scores are still somewhat reflective of moral-cognitive development, the DIT's estimate of liberals' moral-cognitive development is elevated. Future research can continue to explore these hypotheses (e.g., via longitudinal and/or "faking" studies) and, in so doing, further clarify the relationship between Kohlbergian moral reasoning and liberalism-conservatism