Search results for "Borylation"

Synthesis of borylindenides. Complexes with iron and rhenium moieties

1999

Abstract Borylation of lithium indenide with BBrMe 2 gives the allylic 1-indenyl derivative (1-Ind)BMe 2 ( 1c ) together with the bis-allylic connected species (1-Ind) 2 BMe ( 3 ) and with BCl i Pr 2 , the allylic 1-indenyl (1-Ind)B i Pr 2 ( 1d ); the latter, with Et 3 N or Py added, rearranges to the vinylic 3-indenyl isomer (3-Ind)B i Pr 2 ( 2d ). The disubstituted indene C 9 H 6 Ind(SiMe 3 )B(O 2 C 2 Me 4 ) ( 5 ) was prepared from Li[C 9 H 6 B(O 2 C 2 Me 4 )] ( 4b ) and Me 3 SiCl. Both (1-Ind)BMe 2 and (1-Ind)B i Pr 2 readily undergo metalation when treated with LiTMP or LiInd to give pure 1-borylindenides Li(C 9 H 6 BMe 2 ) ( 4c ) and Li(C 9 H 6 B i Pr 2 ) ( 4d ). A barrier to internal …

Synthesis of borylindenides; structure of [Li(N,N′,N″-Me3-1,3,5-C3H6N3)][1-C9H6{B(NMe2)2}]

1998

Abstract Borylation of lithium indenide (LiInd) affords indenylboranes. With BCl(NMe2)2 the primary allylic 1-indenyl derivative IndB(NMe2)2 (1) readily rearranges to the more stable vinylic bis(dimethylamino)(3-indenyl)borane 1′. With BCl(OCMe2)2 the (1-indenyl)-1,3,2-dioxaborolane IndB(OCMe2)2 (2) is obtained. Both indenylboranes 1′ and 2 readily undergo metalation when treated with lithium amides such as LiTMP or LDA to give 1-borylindenides Li[C9H6B(NMe2)2] [Li(3)] and Li[C9H6B(OCMe2)2] [Li(5)] in high yields. In the systems 1′/LiInd and 2/LiInd metalation equilibria are established with equlibrium constants K≈1 (1'/LiInd) and K≈1.4 (2/LiInd). The structure of the solvate [Li(TMHT)][1-C…

Expanding the Variety of Zirconium‐based Inorganic Building Units for Metal–Organic Frameworks

2019

Two new zirconium-based metal-organic frameworks with the composition [Zr6 O4 (OH)4 (OAc)6 (BDC)3 ] (CAU-26) and [Zr5 O4 (OH)4 (OAc)4 (BDC)2 ] (CAU-27) are reported, which were synthesized from acetic acid, a rarely utilized but green and sustainable solvent (BDC2- : 1,4-benzenedicarboxylate). Structure determination aided by automated electron diffraction tomography revealed that CAU-26 is composed of layers of well-known {Zr6 O8 } clusters interconnected by terephthalate ions. In contrast CAU-27 exhibits a three-dimensional structure with a so far unknown type of one-dimensional inorganic building unit (IBU), which can be rationalized as condensed polyhedron-sharing chains of {Zr6 O8 } cl…

Efficient Stereoselective Synthesis of Boron L-Amino Acid Derivatives Using Wittig and Borylation Reactions

2015

The stereoselective synthesis of a new classes of boronato- or trifluoroborato aminoacids and peptides was described using Wittig and C-H iridium borylation as key reactions. A trifluoroborato-thio...

Boron–nitrogen substituted dihydroindeno[1,2-b]fluorene derivatives as acceptors in organic solar cells

2019

The electrophilic borylation of 2,5-diarylpyrazines results in the formation of boron–nitrogen doped dihydroindeno[1,2-b]fluorene which can be synthesized using standard Schlenk techniques and worked up and handled readily under atmospheric conditions. Through transmetallation via diarylzinc reagents a series of derivatives were synthesized which show broad visible to near-IR light absorption profiles that highlight the versatility of this BN substituted core for use in optoelectronic devices. The synthesis is efficient, scalable and allows for tuning through changes in substituents on the planar heterocyclic core and at boron. Exploratory evaluation in organic solar cell devices as non-ful…

Modular Hemisyntheses of Boronato- and Trifluoroborato-SubstitutedL-NHBoc Amino Acid and Peptide Derivatives

2013

Modular hemisyntheses of boronato- and trifluoroborato-substituted amino acid and peptide derivatives by using Wittig and C–H iridium-catalyzed borylation as key reactions, are described. Amino ester precursors bearing an aromatic moiety on a lateral chain were prepared by reaction of a new L-NHBoc-amino acid Wittig reagent with the corresponding aromatic aldehydes. After esterification and hydrogenation, the borylation of amino esters was achieved with yields up to 82 % by using the catalysed reaction of bis(pinacolato) diborane reagent (B2Pin2) in the presence of an iridium complex. Interestingly, this iridium-catalyzed borylation was also performed with a dipeptide in 78 % yield. Finally…

2021

Ruthenium(II) polypyridine complexes are among the most popular sensitizers in photocatalysis, but they face some severe limitations concerning accessible excited-state energies and photostability that could hamper future applications. In this study, the borylation of heteroleptic ruthenium(II) cyanide complexes with alpha-diimine ancillary ligands is identified as a useful concept to elevate the energies of photoactive metal-to-ligand charge-transfer (MLCT) states and to obtain unusually photorobust compounds suitable for thermodynamically challenging energy transfer catalysis as well as oxidative and reductive photoredox catalysis. B(C6F5)(3) groups attached to the CN- ligands stabilize t…

ChemInform Abstract: Efficient Stereoselective Synthesis of Boron L-amino Acid Derivatives Using Wittig and Borylation Reactions

2015

The stereoselective synthesis of a new classes of boronato- or trifluoroborato aminoacids and peptides was described using Wittig and C-H iridium borylation as key reactions. A trifluoroborato-thio...