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The development of selective reactions that utilize easily available and abundant precursors for the efficient synthesis of amines is a long-standing goal of chemical research. Despite the centrality of amines in a number of important research areas, including medicinal chemistry, total synthesis and materials science, a general, selective and step-efficient synthesis of amines is still needed. Here, we describe a set of mild catalytic conditions utilizing a single copper-based catalyst that enables the direct preparation of three distinct and important amine classes (enamines, α-chiral branched alkylamines and linear alkylamines) from readily available alkyne starting materials with high levels of chemo-, regio- and stereoselectivity. This methodology was applied to the asymmetric synthesis of rivastigmine and the formal synthesis of several other pharmaceutical agents, including duloxetine, atomoxetine, fluoxetine and tolterodine. [ABSTRACT FROM AUTHOR]

In the procedure of coal industry production, the losses of the persons and economy caused by the gas explosion accidents are most serious, therefore, prevention and control of the gas explosion accident of the coal mines is an important issue needed to be solved urgently in the safety production work of our coal mines. The characteristic of time structure variation index characteristic was analyzed about gas concentration sequence of three measure points in the NO. II1024 working face. It was found that the value of time variation about three measure points was mostly 1< δ⩽1.5, and gas emission presented consistently strong-clustering state twice, and the value of time variation presented continuous variation state in the active stage of gas concentration. Complex characteristics of the value indicated gas emission was continuously variable in time or space and presented the complex nonlinear characteristics. So the characteristic about gas emission system was correctly depicted and analyzed to gas emission system according to the relation of its state variation and essential of nonlinear system. The result also provided reliable warranty for its continued nonlinear research on gas emission. [ABSTRACT FROM AUTHOR]

A correction to the article "Copper-catalysed selective hydroamination reactions of alkynes" by Shi-Liang Shi and Stephen L. Buchwald is presented.