Regioselective Synthesis of Halotriazoles and their Utility in Metal Catalyzed Coupling Reactions

Abstract

Synthesis of halotriazoles has been studied in the past few decades. Today, coupling reactions such as Heck, Suzuki, Sonogashira, and Stille are important tools in organic synthesis for the construction of C–C bonds. While these coupling reactions have been well utilized with simple haloarenes or halo‐olefins, now they are fast emerging on halotriazoles as well. This review summarizes the development of coupling reactions on halotriazoles, some of which are also biological relevant.

Electronic Coupling in 1,2,3-Triazole Bridged Ferrocenes and Its Impact on Reactive Oxygen Species Generation and Deleterious Activity in Cancer Cells

“… 69 − 73 One of them relies on the palladium-catalyzed Sonogashira cross-coupling reaction of 5-iodo-1,2,3-triazoles with terminal alkynes. 65 , 73 Due to apparent simplicity, we have chosen this approach for the synthesis of compounds 1a and 2a . In the first step, we attempted to obtain the 5-iodo-1,2,3-triazole 1b and 2b intermediates.…”

“…The common feature of 1a – c and 2a – c series of compounds is that they contain the 1,2,3-triazole structural motif. Due to the development of the copper-catalyzed 1,3-dipolar azide–alkyne cycloaddition (CuAAC) reaction, , the interest in the chemistry of 1,2,3-triazoles has increased greatly in the recent time. − In regard to biological applications, 1,2,3-triazoles have proved their value as easy-to-synthesize linkers in bioconjugate chemistry. ,,, In this work, another leap forward has been taken with respect to biological applications of 1,2,3-triazoles as they have been used not only as linkers but also as entities that allow electron transfer between two ferrocenyl groups to occur. The selection of 3′-azido-3′-deoxythymidine (AZT) as the source material for compounds 1a – c was motivated by the biological significance of deoxythymidine nucleoside and general importance of CuAAC reactions in nucleic acid chemistry and biology. , Taking into account the above motivation, compounds 1a and 2a as well as their mononuclear analogues 1c and 2c were used to study their anticancer activity in human A549 and H1975 non-small-cell lung cancer (NSCLC) cells and nonmalignant bronchial epithelium BEAS-2B cells.…”

Chiral Ferrocenyl−Iodotriazoles and −Iodotriazoliums as Halogen Bond Donors. Synthesis, Solid State Analysis and Catalytic Properties.

“…In general, iodotriazoles are obtained by [2+3] cycloaddition between iodoalkynes and alkyl or aryl azides [17] . However, most reported chiral iodotriazoles were produced from chiral azides, [18] derived either from natural substances (carbohydrates, [19] aminoacids, [20] alkaloids [21] ) or from unnatural compounds, such as phenethylamine, [22] cyclohexyldiamine [16g] or BINOL [23] ).…”

Domino assembly of dithiocarbamatesviaCu-catalyzed denitrogenative thiolation of iodotriazole-based diazo precursors

“…5-Iodo-1,2,3-triazoles are well-recognized as readily available synthetic intermediates, 24 providing facile access to fully substituted triazoles and some fused heterocyclic systems. 25 As a part of our current research on 1,2,3-triazole chemistry, 26 we have recently developed a new and convenient approach for the in situ generation of diazo compounds from nucleophile-tethered 5-iodotriazoles, initiated by base-promoted intramolecular substitution.…”