A5072591984- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Organoboron and organosilicon chemistry
- Crystallography and molecular interactions
- Organometallic Complex Synthesis and Catalysis
- Synthesis and characterization of novel inorganic/organometallic compounds
- N-Heterocyclic Carbenes in Organic and Inorganic Chemistry
- Catalytic Cross-Coupling Reactions
- Coordination Chemistry and Organometallics
- Ferrocene Chemistry and Applications
- Chemical Synthesis and Analysis
- Analytical chemistry methods development
- Synthesis and Properties of Aromatic Compounds
- Radical Photochemical Reactions
- Ammonia Synthesis and Nitrogen Reduction
- Boron Compounds in Chemistry
- Synthetic Organic Chemistry Methods
- Ionic liquids properties and applications
Goethe University Frankfurt
2019-2024
The addition of chlorotrimethylsilane to a boron-mediated, transition-metal-free N2 activation reaction leads the isolation multiple potassium boryl(silyl)hydrazido species, likely trapping products terminal dinitrogen complex boron. One these silylated species can be protonated or methylated, providing access mono- tetrafunctionalized hydrazines in two steps from and absence transition metals.
We report a detailed computational and experimental study of the fixation reductive coupling dinitrogen with low-valent boron compounds. Consistent our mechanistic findings, selectivity toward nitrogen or can be controlled through either steric bulk reaction conditions, allowing for on-demand synthesis chains. The electronic structure intriguing magnetic properties intermediates products borylenes are also elucidated using high-level approaches.
Mixed-base-stabilised chloroborylenes are easily accessed by twofold reduction of a cyclic (alkyl)(amino)carbene-supported trichloroborane in the presence second Lewis base, thus enabling fine-tuning electronic properties electron-rich borylene centre.
The N-heterocyclic silylene [{Fe(η5 -C5 H4 -NDipp)2 }Si] (1DippSi, Dipp=2,6-diisopropylphenyl) shows an excellent combination of pronounced thermal stability and high reactivity towards small molecules. It reacts readily with CO2 N2 O, respectively affording (1DippSiO2 )2 C (1DippSiO)2 as follow-up products the silanone 1DippSiO. Its reactions H2 NH3 , FcPH2 (Fc=ferrocenyl) furnish respective oxidative addition 1DippSi(H)X (X=OH, NH2 PHFc). reaction H3 BNH3 unexpectedly results in B-H,...
Ferrocene-based N-heterocyclic plumbylenes fc[(NSiMe2 R)2 Pb:] (1; fc=1,1'-ferrocenylene) are easily accessible by transamination from [(Me3 Si)2 N]2 Pb and the corresponding 1,1'-diaminoferrocene derivatives fc(NHSiMe2 . They may form unconventional dimers 2 a process, which causes cleavage of cyclopentadienyl C-H bond formation Pb-C an N-H bond. The monomer-dimer equilibrium (2 1⇆2) has been addressed experimentally computationally. It critically depends on steric demand N-substituents...
While the dimerization of heavier group 13 carbene analogues to corresponding alkene is known and relatively well understood, dicoordinate borylenes (LRB:, L = neutral donor; R anionic substituent) diborenes (LRB═BRL) has never been directly observed. In this study we present first example a formal borylene-to-diborene through abstraction labile phosphine ligand from tricoordinate hydroborylene precursor (CAAC)(Me3P)BH (CAAC cyclic alkyl(amino)carbene) by bulky Lewis-acidic dihaloboranes...
The recently described crystalline cyclic (alkyl)(amino)carbene with a 1,1’‐ferrocenylene (fc) backbone fc(CPh2–C–NMes) (A, Mes = mesityl) is highly reactive due to its particularly pronounced ambiphilicity and thermally not stable in solution an intramolecular insertion of the divalent carbon atom into methyl C–H bond substituent. closely related congener fc(CPh2–C–N‐p‐C6H4‐tBu) (1) cannot undergo such reaction. Nevertheless, 1 too short‐lived for isolation rapid 1,2‐shift phenyl group,...
Cyclic (alkyl)(amino)carbenes with a 1,1'-ferrocenylene backbone (fcCAACs) are established as an original family by the preparation of crystalline congener. The Ccarbene bond angle is unprecedentedly wide for CAAC, causing exceptionally pronounced ambiphilicity. redox-active opens door to unconventional metalloradicals and oligoradicals.
The reaction of a stable silylene with Ph 2 CCO and OCCCO respectively afforded the first silaallene oxide silylketene, whose hydrolysis furnished methyleneketene.
The reaction of benzoborirene with one equivalent isocyanides leads to benzene-fused boretes bearing imine function, while the two equivalents isocyanide affords 2,3-dihydro-2,3-diiminoboroles perfect regioselectivity. double insertion products represent a novel type 1,2-diimine benzoborole backbone. reduction chemistry benzoborole-supported was investigated. Single- and two-electron allow for isolation full characterization radical anion dianion, respectively. In stark contrast ordinary...
Trichlorosilane is the key intermediate for large-scale production of polycrystalline silicon in Siemens and Union Carbide processes. Both processes, however, are highly inefficient, over two thirds trichlorosilane employed converted to unwanted tetrachloride accumulating millions tons per year on a global scale. In this combined experimental theoretical study we report an energetically environmentally benign synthetic protocol selective conversion SiCl4 HSiCl3 using organohydridosilanes as...
Abstract The parent borylene (CAAC)(Me 3 P)BH, 1 (CAAC=cyclic alkyl(amino)carbene), acts both as a Lewis base and one‐electron reducing agent towards group 13 trichlorides (ECl , E=B, Al, Ga, In), yielding the adducts 1‐ECl increasing proportions of radical cation [1] •+ for heavier analogues. With boron trihalides (BX X=F, Cl, Br, I) undergoes sequential adduct formation halide abstraction reactions to yield borylboronium cations shows an tendency redox processes halides. Calculations...
Reaction of chelating cationic germylene ligand [PhiPDippGe]+ (1; PhiPDipp = {[Ph2PCH2Si(iPr)2](Dipp)N}; Dipp 2,6-iPr2C6H3) with the NHC-stabilised Co0 system [IPr·Co(η2-vtms)2] gives ready access to first example an open-shell metallo-germylene in T-shaped Co complex 2, high yields. Complex 2 is formed through formal oxidative addition Co, giving a unique route this compound class. The centre bears high-spin density its single unpaired electron, corroborated by SQUID magnetometry, EPR...
Abstract The N‐heterocyclic silylene [{Fe(η 5 ‐C H 4 ‐NDipp) 2 }Si] ( 1DippSi , Dipp=2,6‐diisopropylphenyl) shows an excellent combination of pronounced thermal stability and high reactivity towards small molecules. It reacts readily with CO N O, respectively affording O ) C O) as follow‐up products the silanone O. Its reactions NH 3 FcPH (Fc=ferrocenyl) furnish respective oxidative addition (H)X (X=OH, PHFc). reaction BNH unexpectedly results in B−H, instead N−H, bond activation, (H)(BH )....
Abstract Die Reaktion von Benzoborirenen mit einem Äquivalent Isocyanid führt zu benzolkondensierten Boreten einer Iminfunktion, während die zwei Äquivalenten 2,3‐Dihydro‐2,3‐diiminoborole perfekter Regioselektivität ergibt. Isocyanid‐Doppelinsertionsprodukte stellen einen neuen Typ 1,2‐Diiminen Benzoborol‐Rückgrat dar. Reduktionschemie des Benzoborol‐basierenden 1,2‐Diimins wurde untersucht. Reduktion und Elektronen ermöglicht Isolierung vollständige Charakterisierung eines radikalischen...
Graphical Abstract Boron Compounds. The synthesis of 2,3-dihydro-2,3-diiminoboroles through regioselective double insertion isocyanide into benzoborirenes is reported by Max C. Holthausen, Qing Ye et al. in their Communcation (e202312608).