Because of the frequent occurrence of cyclopentane subunits in bioactive compounds, the development of efficient catalytic asymmetric methods for their synthesis is an important objective. Introduced herein is a new family of chiral nucleophilic catalysts, biphenyl-derived phosphepines, and we apply them to an enantioselective variant of a useful [4+1] annulation. A range of one-carbon coupling...

Abstract Carbon–heteroatom (C–X) cross-coupling is a common method for bond-forming reactions in chemistry but the more electronegative heteroatom X is, challenging bond formation becomes. Although reductive elimination from Cu(III) intermediates to form C–X bonds generally facile reaction, oxidative addition of Cu(I) into carbon–(pseudo)halide aryl (pseudo)halides energetically challenging. Th...

in this research, the effect of wood species and particle size on mechanicalproperties of wood plastic composites (wpc) made of fir (abies alba) and beech(fagus orientalis l.) sawdust and high density polyethylene (hdpe) wereinvestigated. wood plastic composite (wpc) were made with 30% hdpe in abatch process at 185˚c, at two particle sizes of 40 mesh and 80 mesh. maleicanhydride polypropylene (...

A new metal-free hydrohalogenation method for alkynes has been developed, which proceeds through a pseudo-intramolecular process. In this reaction, ethynylaniline serves as substrate to quantitatively form an anilinium salt upon treatment with hydrochloric acid. The spatial proximity facilitates the efficient electrophilic addition of HCl ethynyl group in syn-mode, affording corresponding chlor...

To study the interfacial complexity between an agent and its environment such as the adaptive selection aspects of sensory inputs, we propose a new coupling mechanism, called autonomous coupling, where an agent can spontaneously switch on or off its interaction with the environment. An oscillatory neural system with autonomous coupling sums the sensory inputs and initiates action selection via ...

The U.S. Army’s Generalized Intelligent Framework for Tutoring (GIFT) is an important step on the path toward a loosely coupled, serviceoriented system that would promote shareable modules and could underpin multiagent architectures. However, the current version of the system may be “heavier” than it needs to be and not ideal for new or veteran ITS developers. We begin our critique with a discu...

This work investigates the feasibility of using recycled high density polyethylene (rHDPE), recycled polypropylene (rPP) and old newsprint fiber (ONP) to manufacture fiber reinforced composites. The boards were made through air-forming and hot press. The effects of the fiber loading and coupling agent content on tensile, flexural, internal bond properties and water absorption and thickness swel...

Organosilicon reagents are highly versatile and privileged scaffolds in modern synthetic chemistry, largely due to the range of transformations groups amenable to. The β-Silicon effect is one fundamental phenomena underpinning inherent reactivity organosilicon reagents, allowing unsaturated organosilanes undergo a electrophilic substitutions with variety nucleophiles. application organic review...