A novel protocol to prepare multi-substituted dihydrofuropyridine and dihydropyrrolopyridine derivatives from KOH-catalyzed reactions between readily available N-propargylic β-enaminones and arylaldehydes or N-sulfonyl imines has been developed in moderate to good yields.

An efficient, mild, metal-free, base-mediated intramolecular cyclization of N-alkyl, N-propargylic β-enaminones has been realized for the generation of polysubstituted pyrrole derivatives.

Key intermediates, 1-(4-substitutedphenoxyphenyl)ethanamines (9), which were prepared from starting material substituted phenols 4 and p-fluoroacetophenone (5), were condensed with 2-ethoxyethyl 2-cyano-3-ethoxypent-2-enoate (1) or 2-ethoxyethyl-2-cyano-3,3-bis(methylthio)acrylate (2) or 2-ethoxyethyl-3-chloro-2-cyano-4,4,4-trifluorobut-2-enoate (3), giving three series of 2-ethoxyethyl 2-cyano-3-(1-(substitued phenoxyphenyl)ethylamino) alkenates (10, 11 and 12). All of the new compounds have been characterized by H-1 NMR, C-13 NMR, F-19 NMR, IR and HRMS. The herbicidal activities of the title compounds were tested, which indicated that some of the title compounds showed 100% inhibition against Brassica campestris and Amaranthus retroflexus L. at a dose of 93.75 g/ha.

A series of 3‐phenyl benzo[d][1,2,3]triazin‐4( 3H )‐one derivatives were synthesized through the condensation of phenol E and alkyl (alkenyl, alkynyl) chlorides (bromides, iodide) or alkyl chloroacetates or N‐alkyl chloroacetamides using K 2 CO 3 as the acid acceptor in N , N ‐dimethylformamide. Phenol E was prepared from starting material, 5‐amino‐2‐chloro‐4‐fluorophenyl ethyl carbonate, in four steps involving in amidation, reduction, diazotization, and deprotecting‐group reaction. The herbicidal activities of the title compounds were tested against two dicotyledonous plants and two monocotyledonous plants, in which some of them exhibited high herbicidal activities against two dicotyledonous plants in preemergence and postemergence treatments. Moreover, when the dosage was decreased to 180 and 90 g/ha, compounds F1 , F8 , and F9 showed highly selective inhibitory activities against amaranth pigweed, alfalfa, asteraceae, field sowthistle, morning glory, purslane, and velvetleaf in postemergence treatment but had no herbicidal efficacy on rape except F1 , suggesting that it be possible to find a kind of herbicides to inhibit dicotyledonous weeds in the field of dicotyledonous crops with the same genus as aforementioned weeds.

In this Letter, an efficient synthetic route to prepare polysubstituted thiophene derivatives was achieved via the Et3N-mediated (Claisen) rearrangement reaction from alpha-oxo S-methyl-S-propargyl ketenes, which were obtained through alkylation of beta-oxodithioesters with propargylic bromides, followed by regioselective intramolecular cyclization. (C) 2015 Elsevier Ltd. All rights reserved.

A convenient base-mediated strategy to synthesize 3-aryol-4-methyl (or benzyl)-2-methylthio furans 2 (trisubstituted furans) has been developed through the domino coupling/annulations between available α-oxo ketene dithioacetals 1 and propargyl alcohols. In this strategy, these types of bases play an important role in driving the domino coupling reaction of propargyl alcohols and further intramolecular annulations to realize the target compounds. The possible mechanism for the formation of the various products is believed to involve the generation of allenes 7, followed by intramolecular annulations.

In this work, we report the synthesis of mesoporous Bi₂S₃ nanorods under hydrothermal conditions without additives, and investigated their catalytic activities as the CE in DSCs by I-V curves and tested conversion efficiency. To further improve their power conversion efficiency, we added different amounts of reduced graphene by simple physical mixing. With the addition of 9 wt% reduced graphene (rGO), the short-circuit current density, open-circuit voltage and fill factor were Jsc = 15.33 mA cm(-2), Voc = 0.74 V and FF = 0.609. More importantly, the conversion efficiency reached 6.91%, which is slightly inferior to the commercial Pt counter electrode (7.44%). Compared to the conventional Pt counter electrodes of solar cells, this new material has the advantages of low-cost, facile synthesis and high efficiency with graphene assistance. To the best of our knowledge, this Bi₂S₃ + 9 wt% rGO system has the best performance ever recorded in all Bi₂S₃-based CEs in the DSCs system.