Synthesis of Phosphorus(V)-Substituted Six-Membered N-Heterocycles: Recent Progress and Challenges

Heterocycles functionalized with pentavalent phosphorus are of great importance since they include a great variety of biologically active compounds and pharmaceuticals, advanced materials, and valuable reactive intermediates for organic synthesis. Significant progress in synthesis of P(O)R2-substituted six-membered heterocycles has been made in the past decade. This review covers the synthetic strategies towards aromatic monocyclic six-membered N-heterocycles, such as pyridines, pyridazines, pyrimidines, and pyrazines bearing phosphonates and phosphine oxides, which were reported from 2012 to 2022.

Synthesis of para- and meta-imino- or -amino-methyl pyridyl-appended p-tert-butyl-calix[4]arene or p-tert-butyl-thiacalix[4]arene in 1,3-alternate conformation

The multistep synthesis of eight new ligands based on calix[4]arene or thiacalix[4]arene backbones blocked in a 1,3-alternate conformation and bearing four pyridyl units is presented.

Ligands for f-element extraction used in the nuclear fuel cycle

This review describes the latest advances regarding the development, modification and application of suitable ligands for the liquid–liquid extraction of actinides and lanthanides from nuclear waste.

Binding of pyrazine-functionalized calix[4]arene ligands with lanthanides in an ionic liquid: thermodynamics and coordination modes

Complexation thermodynamics of Eu³⁺ with pyrazine-functionalized calix[4]arene in ionic liquid was investigated by absorption spectroscopy, luminescence spectroscopy and microcalorimetry.

Transition metal-catalyzed functionalization of pyrazines

Transition metal-catalyzed reactions are generally used for carbon-carbon bond formation on pyrazines and include, but are not limited to, classical palladium-catalyzed reactions like Sonogashira, Heck, Suzuki, and Stille reactions. Also a few examples of carbon-heteroatom bond formation in pyrazines are known. This perspective reviews recent progress in the field of transition metal-catalyzed cross-coupling reactions on pyrazine systems. It deals with the most important C-C- and C-X-bond formation methodologies.