This is an update to the 2007 Science of Synthesis contribution on F/Hal acetals, and focuses on advances for the synthesis of these compounds that were reported between 2008 and 2023. Such functional units are frequently represented in drugs and materials, and several significant approaches for the synthesis of such compounds that were not covered in the previous chapter have been developed accordingly. Because difluoroalkyl compounds are of particular interest for pharmaceuticals and materials, the advancement of synthetic methods for preparing F/F acetals is occurring more rapidly, and accounts for the major part of this review. [GRAPHICS] .
Cinnoline, also known as 1,2-benzodiazine, is isosteric to traditional all-carbon naphthalene systems. Some synthetic cinnoline-containing compounds have shown biological activity for a diverse collection of targets. In addition to von Richter synthesis, Borsche synthesis, and traditional conditions, more and more transition-metal-catalyzed methods have been developed to prepare cinnolines and functionalize cinnoline-containing compounds. It is also noteworthy that several electrochemical methods have been reported for the synthesis of cinnoline derivatives. [GRAPHICS] .
1,2,3-Triazines, also sometimes known as v- triazines, are characterized by three contiguous nitrogen atoms in the six-membered ring. Benzo[1,2,3]triazines and heteroarenefused 1,2,3-triazine derivatives have found applications in drug development (tulrampator). The reactions of 1,2,3-triazines with primary amines, secondary amines, and thiols make them useful labeling molecules within biological systems. This update covers synthetic methods for the preparation 1,2,3-triazines published between 2013 and 2024. [GRAPHICS] .
Challenging the conventional need for inert atmospheres, dry solvents, and strict temperature control when using s-block organometallic reagents (such as Grignard reagents or organolithium/sodium compounds), this Science of Synthesis review highlights recent advances that enable their operation under air, at room temperature, and in the presence of moisture. Success has been driven by using sustainable protic solvents, such as water and deep eutectic solvents (DESs). These protocols have proven versatile for key organic transformations, including nucleophilic additions to unsaturated molecules, ortho- and lateral lithiation of aromatics, and palladium-catalyzed cross-couplings. Additionally, the development of one-pot tandem hybrid transformations is presented, where these polar s-block organometallic species are effectively integrated with organo-, transition-metal, or biocatalysis. [GRAPHICS] .
1,2,4-Triazines, also known asa-triazines, are a type of unsymmetrical six-membered heterocycle bearing three nitrogen atoms. A series of 1,2,4-triazine frameworks are emerging as core structures in an increasing number of bioactive small molecules such as remdesivir. The application of 1,2,4-triazines as cyclic aza-dienes in inverse-electron-demand Diels-Alder (IEDDA) cycloaddition reactions has been established as a useful method in N-heterocycle synthesis, natural product preparation, and bioorthogonal chemistry. This update covers synthetic methods for the preparation 1,2,4-triazines published between 2013 and 2024. [GRAPHICS] .
