A selective synthesis of 4H-chromenes by the reactions of 2-hydroxychalcone derivatives with acetonitriles substituted with electron-withdrawing groups is described. Under catalyst-free conditions, the reactions give cyano-functionalized 2-aryl-4H-chromenes, whereas in the presence of sodium bicarbonate, 2-amino-4H-chromene-3-carbonitriles are obtained in excellent yields.

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The wider application of conventional electrochemical double-layer supercapacitors is limited by severe self-discharge. Current strategies for tackling self-discharge are mainly focused on each specific component of the device, while a general approach based on configuration design from the device level is largely unknown. Herein, we report a conjugated supercapacitor based on pairs of presodiated manganese oxides with the unique working mechanism of redox pseudocapacitance. Upon aging, the holding time for voltage dropping from 1.0 to 0.4 V for the conjugated device based on Na x δ-MnO2 vs Na1–x δ-MnO2 is four times longer than that of an activated carbon (AC) vs AC device. The successful suppression of self-discharge based on designing device configuration is expected to be universally viable for other capacitive materials.

Selective Synthesis of Cyano-Functionalized 2-Aryl-4H-chromenes and 2-Amino--4H-chromene-3-carbonitriles by Catalyst-Tuned Reactions of 2-Hydroxychalcones with 2-Substituted Acetonitriles. -Depending on the conditions, the reactions provide the title systems selectively. -(YIN*, G.; SHI, H.; XU, L.; WEI, X.; TAO, Q.; Synthesis 45 (2013) 3, 334-340, http://dx.doi.org/10.1055/s-0032-1317945 ; Dep. Chem. Environ. Eng., Hubei Norm. Univ., Huangshi 435002, Hubei, Peop. Rep. China; Eng.) -Mais 21-160

α‐Bromination of aromatic methyl ketones (I) followed by cyclization with thiourea derivatives (II) affords aminothiazole derivatives (III) in moderate to good yields.