Hydroboration of pyridine derivatives at room temperature with earth-abundant and biocompatible magnesium catalysts ligated by phosphinimino amides is developed. Fine turnover frequency (TOF) and distinguished 1,2-regioselectivity have been achieved. The exclusive chemoselective carbonyl hydroboration happens with competitive TOF. A HBpin assisted mechanism is deduced by the reaction rate law, activation parameters, and kinetic isotope effect (KIE) in combination with DFT calculations. To our knowledge, this is the first example of pyridine 1,2-dearomatization by Mg-based catalysts.

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The study on the distribution and dynamic changes of soil moistures and salts under different irrigating methods and managements of using saline groundwater on the sand lands of the hinterland of the Taklimakan Desert, started in 1997. The results show that drip irrigation can be applied to seedlings (furrow irrigation can be applied to level lands) using saline groundwater in the process of constructing the biological shifting sand control system along the desert highway in the hinterland of the Taklimakan Desert; an irrigation frequency of 20 days and an irrigation amount of 30 kg/m 2 ·time are suitable to the shifting sand control forest belts at the same year as they were afforested. Along with the increase of forest age, the irrigation norm can be properly increased, the irrigation interval can be prolonged.

This work describes an electrochemical ammonium cation enabled hydropyridylation of ketone‐activated alkenes under metal‐ and exogenous reductant free conditions giving access to β‐pyridyl ketones, through dual proton‐coupled electron transfer and radical cross‐coupling. It features a broad substrate scope and allows a gram‐scale synthesis. Ammonium chloride plays various roles in this transformation such as the hydrogen donor, the protonation reagent, and electrolyte. In particular, various experiments and density functional theory (DFT) calculation results show the mechanism of dual proton‐coupled electron transfer followed by radical cross‐coupling is the preferred pathway.