A Facile Synthesis of 1,4-Diketones from Organolithium Reagents and N,N,N′,N′-Tetramethylsuccinamide

The reaction of organolithium reagents (alkyl, aryl, heteroaryl) with N,N,N′,N′-tetramethylsuccinamide at 0 °C gives good yields of the corresponding 1,4-diketones.     

Asymmetric fermi surfaces for magnetic schrödinger operators

We consider Schrödinger operators with periodic magnetic field having zero flux through a fundamental cell of the period lattice. We show that, for a generic small magnetic field and a generic small Fermi energy, the corresponding Fermi surface is convex and not invariant under inversion in any point.     

Early Abortion and Personal Ontology

We are beings endowed with “personal capacities”—the capacity for reason, for a concept of self, perhaps more. Among ontologically salient views about what else we are, I focus on the “Big Three.” According to animalism, we are animals that have psychological properties only contingently. According to psychologistic materialism, we are material beings; according to substance dualism, we are either immaterial beings or composites of immaterial and material ones; but according to both psychologistic materialism and substance dualism, we essentially have some psychological properties. I argue that—contrary to what has been argued and is natural to think—none of the Big Three yields different assignments of moral status to early fetuses from any of the others, and consequently the moral status of early abortion doesn’t depend on which (if any) of these views of personal ontology is correct.     

A Far-Infrared Study of the Structures of Tris(Methyl Methyl Phosphonate) Iron(III), Tris(EthylEthylphosphonate) Iron(III), and Tris(IsopropylMethylphosphonate) Iron(III)

In articles by Kokalas et al.^1,2 studies were made of the interaction of FeCl₃ with diisopropyl methylphosphonate (DIMP), diethyl ethylphosphonate (DEEP), and dimethyl methyl phosphonate (DMMP) and structures were proposed for the reaction products. When the reactions are run under much milder conditions, there is much evidence^3–5 to support a different mechanism than that proposed by Kokalas and an altogether different structure of the complexes formed. In the structures proposed by Kokalas et al. the iron atom is surrounded by six oxygen atoms and these are the only bonding atoms to the iron. But on the other hand, in donor-acceptor complexes as are formed in chemisorption reactions,^3–5 some of these sites are filled by chloride ions and this difference should be ascertained quite easily by far-infrared spectroscopy. It was the purpose of this study to look at the far-infrared data and either further substantiate the structures proposed or to propose new ones.     

Bayesian knowledge base tuning

For a knowledge-based system that fails to provide the correct answer, it is important to be able to tune the system while minimizing overall change in the knowledge-base. There are a variety of reasons why the answer is incorrect ranging from incorrect knowledge to information vagueness to incompleteness. Still, in all these situations, it is typically the case that most of the knowledge in the system is likely to be correct as specified by the expert (s) and/or knowledge engineer (s). In this paper, we propose a method to identify the possible changes by understanding the contribution of parameters on the outputs of concern. Our approach is based on Bayesian Knowledge Bases for modeling uncertainties. We start with single parameter changes and then extend to multiple parameters. In order to identify the optimal solution that can minimize the change to the model as specified by the domain experts, we define and evaluate the sensitivity values of the results with respect to the parameters. We discuss the computational complexities of determining the solution and show that the problem of multiple parameters changes can be transformed into Linear Programming problems, and thus, efficiently solvable. Our work can also be applied towards validating the knowledge base such that the updated model can satisfy all test-cases collected from the domain experts.     

Synthesis of 7-Alkoxyquinolines,Coumarins, and Resorufins

Synthesis of the title compounds by treatment of the sodium salts of 7-quinolinol, 7-hydroxycoumarin, and resorufin with alkyl halides is described.     

From Spherical to Leaf‐Like Morphologies: Tunable Supramolecular Assembly of Alkynylgold(I) Complexes through Variations of the Alkyl Chain Length

A series of luminescent polynuclear alkynylgold(I) complexes with different lengths of alkyl chains attached at the N‐heterocyclic carbene moieties has been synthesised and demonstrated to display intriguing self‐assembly behaviours through a cooperative growth mechanism. Variation of the alkyl chain length was found to cause drastic morphological differences in the aggregates and to strongly affect the thermodynamic parameters as revealed by the nucleation–elongation model.     

Rotaxane‐Like Structures Threaded through the Pores of Hollow Porous Nanocapusles

Nanocapsules with molecules threaded through the porous shells may lead to advanced cell‐mimicking functional devices. Herein, we show the feasibility of synthesizing such hybrid nanostructures by using vesicle‐templated polymer nanocapsules with controlled nanopores. Ship‐in‐a‐bottle assembly inside a nanocapsule created an internal unit. An external unit was then connected to an entrapped internal unit through pre‐attached linker threaded through a nanopore in the shell of the nanocapsule. Both internal and external units are larger than the pore size and cannot cross the shell, producing a rotaxane‐like structure. Successful synthesis was achieved with fairly short linkers (six and ten carbon atoms in a chain), creating an opportunity for facile synthesis of functional devices capable of cross‐shell communication.