Inorganometallics (Transition Metal–Metalloid Complexes) and Catalysis

Abstract

While the formation and breaking of transition metal (TM)–carbon bonds plays a pivotal role in the catalysis of organic compounds, the reactivity of inorganometallic species, that is, those involving the transition metal (TM)–metalloid (E) bond, is of key importance in most conversions of metalloid derivatives catalyzed by TM complexes. This Review presents the background of inorganometallic catalysis and its development over the last 15 years. The results of mechanistic studies presented in the Review are related to the occurrence of TM–E and TM–H compounds as reactive intermediates in the catalytic transformations of selected metalloids (E = B, Si, Ge, Sn, As, Sb, or Te). The Review illustrates the significance of inorganometallics in catalysis of the following processes: addition of metalloid–hydrogen and metalloid–metalloid bonds to unsaturated compounds; activation and functionalization of C–H bonds and C–X bonds with hydrometalloids and bismetalloids; activation and functionalization of C–H bonds with vinylmetalloids, metalloid halides, and sulfonates; and dehydrocoupling of hydrometalloids. This first Review on inorganometallic catalysis sums up the developments in the catalytic methods for the synthesis of organometalloid compounds and their applications in advanced organic synthesis as a part of tandem reactions.

Distinct insight into the use of difunctional double-decker silsesquioxanes as building blocks for alternating A–B type macromolecular frameworks

“…These observations are in accordance with the Chalk-Harrod HS mechanism. 22 The conclusions derived from these model reactions were applied in further copolymerization HS and albeit the structures of the obtained products for m = 0 3a-Vi = 3b-H are structurally equal, the reagents built and reaction times varied along with different reaction profiles. We decided to conduct them as a studied model to observe if the electronic and steric effects of Si-H and Si-HCvCH 2 placement in DDSQ substrates affect the formation of copolymeric products.…”

“…While new catalytic methodologies have been developed, hydrosilylation is still one the most important syn-thetic methods of fundamental importance in organosilicon chemistry and also SQ functionalization, mediated by easily available Pt-based Karstedt or Speier catalysts. 22,23 Even though this process is burdened with inconvenience, i.e. selectivity and formation of by-products (derived from side processes, e.g.…”

Zintl cluster supported low coordinate Rh(i) centers for catalytic H/D exchange between H2and D2

“…46 However, the “inorganometallic” chemistry of analogous species with Zintl ions as supporting ligands is essentially unexplored. 47,48 This contribution shows that molecular TMMGAs offer similar rich structural and bond activation chemistry that suggests further study into their uses in catalysis is warranted.…”

Palladium-Catalyzed Oxidative Nonclassical Heck Reaction of Arylhydrazines with Allylic Alcohols via C–N Bond Cleavage: Access to β-Arylated Carbonyl Compounds

“…In the past decades, the palladium-catalyzed Heck coupling reaction has emerged as an efficient method for carbon–carbon bond formation since the seminal studies of Heck and Mizoroki in 1960s . Among them, the palladium-catalyzed aryl Heck reaction of terminal alkenes has been well-explored for the construction of E -styrene compounds . In this reaction, 1-positon β-H elimination of the 2-Pd-alkyl intermediate is always favored due to the conjugated structure of styrene, thus called the “classic Heck reaction” (Scheme a, left). , On the other hand, a nonclassical 3-position β-H elimination is more prone to occur when a special OH group is installed at the 3-position of alkene (Scheme a, right) because the hydroxyl group provides the necessary driving force to access β-arylated carbonyl compounds, which is one of the key structural motifs found in pharmaceuticals and biologically active natural products .…”