Synthesis and properties of new fused pyrrolo-1,10-phenanthroline type derivatives

New fused pyrrolo-phenanthroline type derivatives were synthesized, in two steps, from 1,10-phenanthroline and evaluated for antimicrobial activity and fluorescence properties. Our synthetic approach involved a 3+2 dipolar-cycloaddition of some selected N-substituted 1,10-phenanthrolin-1-ium ylides, (m)ethoxycarbonyl and cyano (1,2-di)substituted acetylenes and alkenes, respectively. The structures of compounds were supported by analytical and spectroscopic data. Molecular structures of four compounds have also been also determined by monocrystal XRD analyses. All synthesized compounds were then evaluated for their potential antimicrobial activity against Staphylococcus aureus ATCC25923, Escherichia coli ATCC25922 and Candida albicans ATCC10231. Two of the compounds demonstrated good activity against the above tested strains.

Azaheterocyclic Derivatives of ortho-Carborane: Synthetic Strategies and Application Opportunities

Azaheterocyclic derivatives of 1,2-dicarba-closo-dodeca­borane (ortho-carborane) are known to be of particular interest due to numerous plausible applications, particularly, in medicine, materials science, and advanced technologies. Three principal synthetic strategies resulting in azaheterocyclic carboranes, in which boron-enriched and azaheterocyclic fragments are linked to each other, either directly by means of the C–C bonds or through a short spacer (CH2, CH2S, CH2O, etc.), have been outlined. These synthetic approaches are of general character and can be used both individually and in combination to afford promising organoboron clusters of diverse architectures.1 Introduction2 C–C Cross-Coupling Strategies in the Synthesis of Azahetero­cyclic Carboranes3 Carboryne-Based Transformation Strategies4 Condensation Strategies: Reactions of Decaborane B10H14 with Substituted Acetylenes5 Conclusion and Outlook

Dimerization of boryl- and amino-substituted acetylenes by B2C2 four-membered ring formation

Boryl- and amino-substituted acetylenes bearing diphenylboryl or 9-borabicyclononyl groups were synthesized.

Transition-metal-free one-pot synthesis of alkynyl selenides from terminal alkynes under aerobic and sustainable conditions

Alkynyl selenides were synthesized by a straightforward one-pot and three-step methodology, without the need of diselenides as starting reagents, under an oxygen atmosphere and using PEG 200 as the solvent. This procedure involves the in situ generation of dialkyl diselenides through a K3PO4-assisted reaction of an alkyl selenocyanate obtained by a nucleophilic substitution reaction between KSeCN and alkyl halides. Successive reaction with terminal alkynes in the presence of t-BuOK affords the corresponding alkyl alkynyl selenide in moderate to good yields. Finally, this methodology allowed the synthesis of 2-alkylselanyl-substituted benzofuran and indole derivatives starting from convenient 2-substituted acetylenes.

One-pot synthesis of propynoates and propynenitriles

An efficient transformation towards propynoates and propynenitriles is herein described. The practical methodology was conducted at low temperature (–78 or –60 °C) in a one-pot manner with the assistance of base rather than any transition metal catalysts. The base-induced protocol exhibits good functional group tolerance (up to 28 examples) and high efficiency (up to 92% yields) towards substituted acetylenes of great synthetic significance, which was also well demonstrated by the gram-scale reactions.