The Role of Monoanionic Aryl Pincer Ligands in the Stabilization of Group 14 Metallylenes

Abstract

Pincer ligands have an important role in stabilizing group 14 metallylenes. The particular structure of the aryl pincer ligands makes them a unique ligand platform. This review is focused on presenting monoanionic metallylenes stabilized by aryl pincer‐type ligands, described so far in the literature, with focus on their synthesis, structural features, and reactivity. Throughout this work, the close correlation between structure and reactivity is highlighted, as well as the manner in which this influences the stability of the compounds and their potential applications.

Ambiphilic Nature of Dipyrrolylpyridine-Supported Divalent Germanium and Tin Compounds

“…A review by Madec and Nemes summarized recent advances in the area of group 14 compounds supported by monoanionic aryl pincer type ligands. 27 Notably, these ligands were found to effectively stabilize low-valent species. In this context, singly bonded Sn(I) species 32−35 In addition, we previously reported the synthesis of low-valent, pincer ligand supported tritin complexes [(dpp Ph Sn) 3 ] + X − (dpp Ph = 2,5-di(o-pyridyl)-3,4-diphenylpyrrolate; X = Cl, OTf, PF 6 , and AlCl 4 ), which contain two Sn−Sn linkages nearly perpendicular to the dpp Ph ligand planes.…”

“…A review by Madec and Nemes summarized recent advances in the area of group 14 compounds supported by monoanionic aryl pincer type ligands . Notably, these ligands were found to effectively stabilize low-valent species.…”

Synthesis and Characterization of a Novel Bis‐Sulfoxide and Its Evaluation as a Ligand in p‐Block Chemistry

“…This observation also suggests that coordination of the oxygen atoms of the sulfinyl groups is likely in compound 5 , as it was proven for the sulfone‐sulfoxide stannylene . The chemical shift for 5 observed at 75 and 54 ppm are downfield shifted compared to other O,C,O‐chelating chlorostannylenes (–99 ppm) , . Furthermore, in the mass spectrum peaks for [M + CH 3 OH] + (C 24 H 26 O 2 S 2 SnCl + CH 3 OH) at 597.0, [M – Cl] (C 24 H 25 O 2 S 2 Sn) at 529.0 and a dimeric species [C 48 H 50 O 4 S 4 Sn] + at 939.2 can be observed (See S11 ESI), species that suggest the existence of the stannylene in the mixture.…”

“…[43] The chemical shift for 5 observed at 75 and 54 ppm are downfield shifted compared to other O,C,O-chelating chlorostannylenes (-99 ppm). [60,61] at 939.2 can be observed (See S11 ESI), species that suggest the existence of the stannylene in the mixture. However, due to the sensitivity of the products, the mixture could not be separated and purified, thus further analysis was not realized.…”

The reactivity of antimony and bismuthN,C,N-pincer compounds toward K[BEt3H] – the formation of heterocyclic compoundsvs. element–element bondsvs.stable terminal Sb–H bonds

“…4 They also found applications among p-block elements, where their rigid terdentate coordination pocket allowed isolation of many spectacular compounds with interesting reactivity. 5…”