The direct arylation of substituted pyridines with several arylboronic acids has been developed. This transformation could proceed readily at ambient temperature using inexpensive reagents: iron(II) oxalate as a catalyst, potassium persulfate as a co‐oxidant, which can afford the arylated products in mild to good yields. The mechanism is presumed to proceed through a nucleophilic radical addition to the pyridines with in situ reoxidation.

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Alkylaryl sulfonate is a typical family of surfactants used for chemically enhanced oil recovery (EOR). While it has been widely used in surfactant–polymer flooding at Karamay Oilfield (40 °C, salinity 14,000 mg/L), its aggregation behavior in aqueous solutions and the contribution of aggregation to EOR have not been investigated so far. In this study, raw naphthenic arylsulfonate (NAS) and its purified derivatives, alkylaryl monosulfonate (AMS) and alkylaryl disulfonate (ADS), were examined under simulated temperature and salinity environment of Karamay reservoirs for their micellar aggregation behavior through measuring surface tension, micellar size, and micellar aggregation number. It was found that all three alkylaryl sulfonate surfactants could significantly lower the surface tension of their aqueous solutions. Also, it has been noted that an elevation both in temperature and salinity reduced the surface tension and critical micellar concentration. The results promote understanding of the performance of NAS and screening surfactants in EOR.

An efficient, metal-free C-H halogenated method for the synthesis of β-halogenated carboxamides using non-corrosive NXS (X=Cl, Br) as the halogenated source and ammonium sulfocyanide (NH 4 SCN) as the additive was proposed and accomplished. Various substituted 2-oxazolines efficiently afforded the corresponding β-halogenated carboxamides via a ring-opening reaction in good yields. The characteristic features of this reaction include readily available materials, mild reaction conditions and functional groups tolerance.[a] Dr.

L-lactate is one of main byproducts excreted in to the fermentation medium. To improve L-glutamate production and reduce L-lactate accumulation, L-lactate dehydrogenase-encoding gene ldhA was knocked out from L-glutamate producing strain Corynebacterium glutamicum GDK-9, designated GDK-9ΔldhA. GDK-9ΔldhA produced approximately 10.1% more L-glutamate than the GDK-9, and yielded lower levels of such by-products as α-ketoglutarate, L-lactate and L-alanine. Since dissolved oxygen (DO) is one of main factors affecting L-lactate formation during L-glutamate fermentation, we investigated the effect of ldhA deletion from GDK-9 under different DO conditions. Under both oxygen-deficient and high oxygen conditions, L-glutamate production by GDK-9ΔldhA was not higher than that of the GDK-9. However, under micro-aerobic conditions, GDK-9ΔldhA exhibited 11.61% higher L-glutamate and 58.50% lower L-alanine production than GDK-9. Taken together, it is demonstrated that deletion of ldhA can enhance L-glutamate production and lower the unwanted by-products concentration, especially under micro-aerobic conditions.