A divergent procedure for multicomponent synthesis of novel ferrocenyl derivatives of dicyanoanilines and cyanopyridines

Aqueous/Nonaqueous DBU Mixtures: Versatile Switching Media for Chemoselective Aldol, Baylis-Hillman, and Aldol Condensation Reactions

Isophorone is a relatively small molecule with several neighboring reacting sites, making it susceptible to various competing reactions with aldehydes, including aldol, Baylis-Hillman (BH), aldol condensation, and Michael addition reactions. In the present work, we have designed a switchable 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)-catalyzed procedure, where the reaction of isophorone with aldehydes is guided chemoselectively toward either aldol, BH, or aldol condensation reactions, depending on the use of water and/or heat. This controllable divergency likely stems from the ability to tune the dual nucleophilicity/basicity characters of the DBU/H2O medium. In other words, the nucleophilicity of DBU plays a crucial role in directing the process toward the formation of the BH adducts in the absence of water. At the same time, the aldol pathway dominates when water is present. The conditions were amenable for tandem processes, as demonstrated for an aldol condensation/Diels-Alder sequence.

Synthesis, properties, and application of the new nanocatalyst of double layer hydroxides in the one-pot multicomponent synthesis of 2-amino-3-cyanopyridine derivatives

A new heterogeneous nanocatalyst LDH@3-chloropyltrimethoxysilane@1,3-benzenedisulfonyl amine@Cu (LDH@TRMS@BDSA@Cu) was synthesized and confirmed by analyzes such as Fourier transform infrared spectroscopy, Field Emission Scanning Electron Microscopy, energy scattered X-ray spectroscopy (EDX), elemental mapping, X-ray diffraction analysis, heat gravity/heat derivatization (TGA) and differential scanning calorimetry. The newly synthesized nanocatalyst effectively catalyzed the reaction between different aryl aldehydes, malononitrile, different acetophenones and ammonium acetate in solvent-free conditions and they were converted into 2-amino-3-cyanopyridine derivatives with high efficiency. The reaction showed advantages such as simplicity, high stability, environmental friendliness, excellent efficiency and short time. Also, this catalyst is recyclable and was recycled 4 times without losing significant catalytic power.

Four-component one-pot synthesis of novel dicyanoaniline anchored triazoles

A four-component reaction was developed by taking the advantage of the reactivity of the propargyl functional groups, residing on the primarily formed dicyanoaniline products. Various enolizable cyclic ketones were reacted with malononitrile and 4-(prop-2-yn-1-yloxy)benzaldehyde derivatives in an aqueous <i>t</i>-BuOH/NaOH medium, and the resulting dicyanoanilines were subjected to a subsequent in situ click reaction to afford the final dicyanoaniline-anchored-triazole products. The enhanced photophysical properties of the novel products are under current study.