Synthesis of silylbut-1-en-3-ynes and buta-1,3-dienes as building blocks via hydrosilylation of 1,4-bis(trimethylsilyl)buta-1,3-diyne.

The selective and efficient synthesis of (E)-1,2,4-trisilylbut-1-en-3-ynes obtained via Pt-catalyzed hydrosilylation of 1,4-bis(trimethylsilyl)buta-1,3-diyne is described. Optimized reaction conditions (Pt(PPh)) or Pt(dvs), 100 °C, toluene, 18 h) yielded compounds with high isolation yields (76-95%). The modification of (E)-1,2,4-trisilylbut-1-en-3-ynes was further tested in protodesilylation, halodesilylation, hydrosilylation, and Pd-based cross-coupling reactions, resulting in a broad spectrum of new products.

Modular Synthesis of New Metalloid-Substituted Olefins from Diboryl(Silyl)Ethenes via Suzuki-Miyaura Reactions.

A novel approach towards synthesizing new metalloid-substituted olefins has been accomplished by transforming ()-1,2-diboryl-1-silylethenes through two consecutive Suzuki-Miyaura coupling reactions. This methodology provides an effective and selective way to obtain new, structurally different products, such as ()-1-silyl-1-boryl-2-arylethens, (1)-1-silyl-1-boryl-2-alkenylethens, and ()-1-silyl-1-aryl-2-arylethenes, which are difficult to synthesize through hydrometallation reactions and related processes. Due to the presence of reactive motifs (silyl group, Bpin moiety, and C-H bond) in the structure of the final products, these molecules might be considered powerful building blocks in modern chemistry.

Preparation of T and double-decker silsesquioxane-based Janus-type molecules: molecular modeling and DFT insights.

We present a methodology for the synthesis of inorganic-organic Janus-type molecules based on mono-T and difunctionalized double-decker silsesquioxanes (DDSQs) via hydrosilylation reactions, achieving exceptionally high yields and selectivities. The synthesized compounds were extensively characterized using various spectroscopic techniques, and their sizes and spatial arrangements were predicted through molecular modelling and density functional theory (DFT) calculations. Quantum chemical calculations were employed to examine the interactions among four molecules of the synthesized compounds.

Magnetically Recyclable Borane Lewis Acid Catalyst for Hydrosilylation of Imines and Reductive Amination of Carbonyls.

Fluorinated arylborane-based Lewis acid catalysts have shown remarkable activity and serve as ideal examples of transition metal-free catalysts for diverse organic transformations. However, their homogeneous nature poses challenges in terms of recyclability and separation from reaction mixtures. This work presents an efficient technique for the heterogenization of boron Lewis acid catalysts by anchoring Piers' borane to allyl-functionalized iron oxide.

Pt(PPh) and Pt(PPh)@IL catalyzed hydroboration of ketones.

An efficient method for the reduction of various ketones via [Pt(PPh)]-catalyzed hydroboration with HBpin has been successfully developed for the first time. The protocol is suitable for symmetrical and unsymmetrical derivatives possessing electron donating or withdrawing functional groups. O-borylated products were easily converted to 2° alcohols via hydrolysis with high isolated yields.

Reactivity of a series of triaryl borates, B(OAr), in hydroboration catalysis.

In this paper, we compare the reactivity of a series of triaryl borates B(OAr) as catalysts for the hydroboration of alkenes and alkynes. It was observed that commercially available B(OPh) performed the poorest, whereas catalysts with -F atoms appeared to perform much better.

Selective synthesis of boron-substituted enynes a one-pot diboration/protodeboration sequence.

An efficient and facile one-pot protocol to access enynylboronates a Pt-catalyzed diboration/protodeboration strategy has been developed. The reaction is suitable for various silylsubstituted symmetrical and unsymmetrical 1,3-diynes, leading to π-conjugated organoboron compounds with excellent regio- and stereoselectivity.

Synthesis of unsymmetrically and symmetrically functionalized disiloxanes via subsequent hydrosilylation of C≡C bonds.

A selective synthesis of unsymmetrically functionalized disiloxanes via the subsequent hydrosilylation of internal alkynes in the first step, and alkynes (terminal or internal) or 1,3-diynes in the second, with 1,1,3,3-tetramethyldisiloxane (1) is presented for the first time. Using developed approaches performed in a stepwise or one-pot manner a new family of disubstituted disiloxanes was obtained which had previously been inaccessible by other synthetic methods. Moreover, symmetrically functionalized disiloxanes were obtained by direct hydrosilylation of 2 equivalents of terminal or internal alkynes with 1, showing the unique versatility of the hydrosilylation process.

Directed -hydrosilylation of borylalkynes to borylsilylalkenes.

Hydrosilylation of borylalkynes to borylsilylalkenes (with a different arrangement of substituents) has been successfully developed. The -addition of SiH group to the CC bonds was directed by using a specific catalyst. The obtained products are crucial synthons for the introduction of the CC bonds in organic synthesis.

[Pt(PPh)]-Catalyzed Selective Diboration of Symmetrical and Unsymmetrical 1,3-Diynes.

A straightforward, efficient, and selective method for the preparation of novel boryl-functionalized enynes or dienes via [Pt(PPh)]-catalyzed diboration of a broad spectrum of symmetrical and unsymmetrical 1,3-diynes was developed. The catalytic cycle of diboration was proposed on the basis of low-temperature P NMR studies. An alternative isolation method via product condensation on a cold finger was developed, which, in contrast to previous literature reports, eliminates the need for the additional transformation of rapidly decomposing enynyl pinacol boronates to more stable silica-based column chromatography derivatives during the separation step.

Hydroelementation of diynes.

This review highlights the hydroelementation reactions of conjugated and separated diynes, which depending on the process conditions, catalytic system, as well as the type of reagents, leads to the formation of various products: enynes, dienes, allenes, polymers, or cyclic compounds. The presence of two triple bonds in the diyne structure makes these compounds important reagents but selective product formation is often difficult owing to problems associated with maintaining appropriate reaction regio- and stereoselectivity. Herein we review this topic to gain knowledge on the reactivity of diynes and to systematise the range of information relating to their use in hydroelementation reactions.

Alkenyl-Functionalized Open-Cage Silsesquioxanes (RSiMeO)R'SiO: A Novel Class of Building Nanoblocks.

Trifunctional incompletely condensed polyhedral oligomeric silsesquioxanes (RSiMeO)R'SiO (s) are considered as intriguing building nanoblocks dedicated to constructing highly advanced organic-inorganic molecules and polymers. Up to now, they have been mainly obtained hydrosilylation of olefins, while the hydrosilylation of the C≡C bonds has not been studied at all, despite the enormous potential of this approach resulting from the possibility of introducing 3, 6, or even more functional groups into the structure. Therefore, in this work, we present a highly selective and efficient synthesis of the first example of tripodal alkenyl-functionalized s, obtained platinum-catalyzed hydrosilylation of the terminal and internal alkynes, as well as symmetrically and nonsymmetrically 1,4-disubstituted buta-1,3-diynes with silsesquioxanes (HSiMeO)R'SiO (R' = -CH (), (HC)CHC(HC)HCHC ()).

Synthesis of bifunctional disiloxanes via subsequent hydrosilylation of alkenes and alkynes.

The first protocol for the synthesis of unsymmetrical bifunctional 1,1,3,3-tetramethyldisiloxane derivatives via subsequent hydrosilylation of alkenes and alkynes is presented. The methodology described has vast functional group tolerance and is extremely efficient towards the formation of novel disiloxane-based building blocks.

Application of Green Solvents: PEG and scCO in the Mono- or Biphasic Catalytic Systems for the Repetitive Batch Coupling of Vinylsilanes with Vinyl Boronates toward 1-Boryl-1-silylethenes.

A new method for the repetitive batch silylative coupling (trans-silylation) of vinylsilanes with vinyl boronates in the presence of Ru(CO)Cl(H)(PCy) immobilized in poly(ethylene glycols) (PEGs) has been developed. Three PEGs (PEG600, PEG2000, and MPEG2000) with different molecular weights and end groups (MW = 600-2000) were tested as solvents and immobilization media, while an aliphatic solvent (-hexane or -heptane) or supercritical CO was used for product extraction. By applying 2 mol % of the Ru-H catalyst, it was possible to carry out up to 15 complete runs, with the predominant formation of 1-boryl-1-silylethenes.

Pt-Catalyzed Hydrosilylation of 1,3-Diynes with Triorganosilanes: Regio- and Stereoselective Synthesis of Mono- or Bis-silylated Adducts.

An efficient method has been successfully developed for the functionalization of various 1,3-diynes by the hydrosilylation reaction with triethyl- or triphenylsilane catalyzed by Pt catalysts (Pt(dvs), PtO, or Pt(PPh)). Comprehensive optimization studies were performed for the first time to find suitable process conditions for the stereo- and regioselective formation of mono- or bis-silylated adducts from commercially available substrates and catalysts. Silyl-substituted 1,3-enynes or bis-silyl-functionalized buta-1,3-dienes were obtained with excellent yields and fully characterized.

Selective Hydrosilylation of Alkynes with Octaspherosilicate (HSiMe O) Si O.

Comprehensive studies on platinum-catalyzed hydrosilylation of a wide range of terminal and internal alkynes with spherosilicate (HSiMe O) Si O (1 a) were performed. The influence of the reaction parameters and the types of reagents and catalysts on the efficiency of the process, which enabled the creation of a versatile and selective method to synthesize olefin octafunctionalized octaspherosilicates, was studied in detail. Within this work, twenty novel 1,2-(E)-disubstituted and 1,1,2-(E)-trisubstituted alkenyl-octaspherosilicates (3 a-m, 6 n-t) were selectively obtained with high yields, and fully characterized ( H, C, Si NMR, FTIR, MALDI TOF or TOF MS ES analysis).

Recent Advances in Boron-Substituted 1,3-Dienes Chemistry: Synthesis and Application.

In the syntheses developed to access naturally occurring compounds, especially bioactive substances, boron-functionalized dienes (also "linchpin" reagents) are used as key reagents. Structurally unique dienes are found in nature, and play important biological and chemical roles. Recently, linchpin moieties have been proved as useful substrates for a variety of highly functionalized chemical transformations.

A stereoselective synthesis of (E)- or (Z)-β-arylvinyl halides via a borylative coupling/halodeborylation protocol.

A new stereoselective method for the synthesis of (E)-β-arylvinyl iodides and (E)- or (Z)-β-arylvinyl bromides from styrenes and vinyl boronates on the basis of a one-pot procedure via borylative coupling/halodeborylation is reported. Depending on the halogenating agent as well as the mode of the halodeborylation reaction, (E) or (Z) isomers are selectively formed.

(E)-9-(2-iodovinyl)-9H-carbazole: a new coupling reagent for the synthesis of π-conjugated carbazoles.

The one-pot synthesis of (E)-9-(2-iodovinyl)-9H-carbazole via sequential ruthenium-catalyzed silylative coupling of N-vinylcarbazole with vinyltrimethylsilane and iododesilylation is reported. Its use as a new building block in the palladium-catalyzed Sonogashira and Suzuki-Miyaura coupling reactions to yield new carbazole-containing (E)-but-1-en-3-ynes and (E,E)-buta-1,3-dienes is demonstrated.

A new catalytic route to boryl- and borylsilyl-substituted buta-1,3-dienes.

Vinyl-substituted boronates in the presence of complexes containing Ru-H bonds (preferably [Ru(CO)ClH(PCy(3))(2)], Cy: cyclohexyl) react regioselectively with terminal ethynes (involving silylethynes), albeit with the exception of phenylacetylene, to produce boryl- and borylsilyl-substituted buta-1,3-dienes with a preference for E,E-diene. The reaction opens a new catalytic route for the preparation of dienylboronates, and particularly dienylsilylboronates, that are functionalised building blocks in the synthesis of organic and natural products. The mechanism of this new reaction was proved to involve an insertion of alkyne into Ru-H bonds followed by an insertion of coordinated vinyl boronate into the Ru-C= bond and beta-hydrogen transfer to the metal to eliminate boryldiene or borylsilyldiene.

New catalytic route to borasiloxanes.

A new, highly selective method for effective synthesis of boryl silyl ethers (borasiloxanes) via O-borylation of silanols with vinylboronates catalyzed by the Ru-H complexes [RuHCl(CO)(PCy3)2] and [RuHCl(CO)(PPh3)3] is described.