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A divergent procedure was developed for multicomponent reaction of ferrocenecarboxaldehyde with malononitrile and various cyclic ketones. Ultrasonic irradiation of 1.0:1.0:2.0 ethanolic mixtures of the reactants produced dicyanoanilines 4 chemoselectively in high yields, while equimolar mixtures of the same reactants in refluxing EtOH solely resulted in four‐component formation of cyanopyridines 5. Both series of products are obtained directly by spontaneous precipitation in the reaction mixtures avoiding cumbersome and expensive chromatographic separations. [ABSTRACT FROM AUTHOR]

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Abstract: Ultrasonic irradiation was efficiently used for high yield synthesis of monoarylidene derivatives of cyclic systems directly from the reaction of ketone with various aldehydes under solvent-free conditions. Reactions took place rapidly in the presence of catalytic amounts of pyrrolidine, while no significant formation of the undesired bis by-products was observed. Moreover, the procedure was applicable to both homo- and heterocyclic ketones. [Copyright &y& Elsevier]

An efficient and room-temperature procedure is developed for high yield synthesis of novel α,β-unsaturated derivatives of thiopyran 3 directly from ketone 1 and various aldehydes in the presence of catalytic quantities of TMSNMe2 and MgBr2⋅OEt2 under solvent-free conditions. The main advantage of the procedure is that the formation of the undesired bis by-products is minimized. In addition, the procedure is applicable to other enolizable carbocyclic and acyclic ketones. [ABSTRACT FROM AUTHOR]

Non-thermal, solvent-free condensation of several aryl methyl ketones with amines and elemental sulfur is efficiently conducted using ultrasonic irradiation within short time periods. Consequently, various thioacetamides are conveniently synthesized. Similar experiments at controlled temperature (25 ± 1° C) resulted in comparable yields, showing the promotional role of ultrasound irradiation in the progress of the reaction. GRAPHICAL ABSTRACT [image omitted] [ABSTRACT FROM AUTHOR]

An efficient four-component reaction was developed to take advantage of the reactivity of the 2-aminothiophene-3-carbonitrile functionality, which is obtained during the classical three-component Gewald reaction. Various α-methylene bearing ketones were reacted with malononitrile, elemental sulfur, and aryl/heteroarylnitrile derivatives in t -BuOH/NaOH to afford 2-arylthieno[2,3- d ]pyrimidin-4-amines in high yields. Preliminary studies revealed the photophysical properties of the products and their potential for use as metal sensors. [ABSTRACT FROM AUTHOR]

A series of novel ( E )-5,5-dimethyl-3-styrylcyclohex-2-en-1-ol dienes were synthesized by reduction of the respective ketones and their Diels–Alder reactivity explored with N -phenylmaleimide and methyl acrylate. Consequently, two groups of novel products were synthesized in high yields. In reactions with N -phenylmaleimide, the initially formed cycloadducts undergo an additional in situ lactonization to give tricyclic lactone systems, due to spontaneous attack of the allylic hydroxyl on the neighboring carbonyl group of the dienophile residue. All reactions proceeded stereoselectively to give solely the endo products. [ABSTRACT FROM AUTHOR]