Zur Kenntnis der Chemie der Metallcarbonyle in flüssigem Ammoniak, XII. Die Reaktionen der Hexacarbonyle der Chromgruppe und ihrer Bipyridyl‐(2.2′)‐ und 1.10‐Phenanthrolin‐Substitutionsprodukte im Ammonosystem

Behrens, H.; Harder, Norbert

doi:10.1002/cber.19640970217

Cited by 32 publications

(2 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To explore whether the B–H bond of a neutral BH 3 ·L group also has a ligand field strength comparable to that of ammonia, we carried out similar ETS-NOCV analysis on the known compounds Cr(CO) 5 (BH 3 NMe 3 ) (in which the BH 3 NMe 3 group is bound to Cr through a κ 1 -BH 3 group) and Cr(CO) 5 (NH 3 ). , In both compounds (see the Supporting Information for details), the main interaction between the Cr(CO) 5 and L fragments is donation into a Cr d orbital of electron density from a B–H bond (for L = BH 3 NMe 3 ) or a N lone pair (for L = NH 3 ) (Tables S16 and S17). The electron transfer eigenvalues for these L → M interactions are 0.40 and 0.35 for L = BH 3 NMe 3 and NH 3 , respectively; the net electron transfer from L to Cr (taking into account the small amounts of M → B–H* or N–H* interaction) is 0.21 for L = BH 3 NMe 3 and 0.19 for L = NH 3 (Table S18).…”

Section: Resultsmentioning

confidence: 99%

Three-Center M–H–B Bonds Are Strong Field Interactions. Synthesis and Characterization of M(CH₂NMe₂BH₃)₃ Complexes of Titanium, Chromium, and Cobalt

Lastowski,

Yarranton,

Zhu

et al. 2023

J. Am. Chem. Soc.

View full text Add to dashboard Cite

We describe new compounds of stoichiometry M(CH2NMe2BH3)3 (M = Ti, Cr, and Co), each of which contains three chelating boranatodimethylaminomethyl (BDAM) ligands. In all three compounds, the BDAM anion, which is isoelectronic and isostructural with the neopentyl group, is bound to the metal center at one end by a metal–carbon σ bond and at the other by one three-center M–H–B interaction. The crystal structures show that the d1 titanium(III) compound is trigonal prismatic (or eight-coordinate, if two longer-ranged M···H interactions with the BH3 groups are included), whereas the d3 chromium(III) compound and the d6 cobalt(III) compounds are both fac-octahedral. The Cr and Co compounds exhibit two rapid dynamic processes in solution: exchange between the Δ and Λ enantiomers and exchange of the terminal and bridging hydrogen atoms on boron. For the Co complex, the barrier for Δ/Λ exchange (ΔG ⧧ 298 = 10.1 kcal mol–1) is significantly smaller than those seen in other octahedral cobalt(III) compounds; DFT calculations suggest that Bailar twist and dissociative pathways for Δ/Λ exchange are both possible mechanisms. The UV–vis absorption spectra of the cobalt(III) and chromium(III) species show that the ligand field splittings Δo caused by the M–H–B interactions are unexpectedly large, thus placing them high on the spectrochemical series (near ammonia and alkyl groups); their nephelauxetic effect is also large. The DFT calculations suggest that these properties of M–H–B interactions are in part a consequence of their three-center nature, which delocalizes electron density away from the metal center and reduces electron–electron repulsions.

show abstract

Section: Resultsmentioning

confidence: 99%

Three-Center M–H–B Bonds Are Strong Field Interactions. Synthesis and Characterization of M(CH₂NMe₂BH₃)₃ Complexes of Titanium, Chromium, and Cobalt

Lastowski,

Yarranton,

Zhu

et al. 2023

J. Am. Chem. Soc.

View full text Add to dashboard Cite

show abstract

“…For the ligands with the highest affinity toward molybdenum(0), overreaction was sometimes observed, yielding products not containing any DAD ligands. IR spectra indicated the formation of [Mo(CO) 3 L 3 ] in these cases . To overcome this problem, 2 was used as a precursor, giving good yields of the desired complexes (methods D and E).…”

Section: Resultsmentioning

confidence: 99%

Molybdenum 1,4-Diazabuta-1,3-diene Tricarbonyl Solvento Complexes Revisited: From Solvatochromism to Attractive Ligand–Ligand Interaction

Oelkers

Venker

2012

Inorg. Chem.

View full text Add to dashboard Cite

Various complexes of the types [Mo(DAD)(CO)(3)L] (L = CO, MeCN, MeOH, THF, DMSO, DMF, Me(2)CO, EtOAc, THT, Im(H), Im(1), tBuNC, nBu(3)P), (ER(4))[Mo(DAD)(CO)(3)X] (ER(4) = NEt(4)(+); X(-) = Cl(-), Br(-), I(-), NCS(-), CN(-) and ER(4)(+) = PPh(4)(+); X(-) = N(3)(-)), and (ER(4))[{Mo(DAD)(CO)(3)}(2)(μ-X)] (ER(4)(+) = NEt(4)(+); X(-) = CN(-), OAc(-) and ER(4)(+) = PPh(4)(+); X(-) = N(3)(-); DAD = N,N'-bis(2,6-dimethylphenyl)butane-2,3-diimine) were prepared by ligand exchange from cycloheptatriene molybdenum tricarbonyl. A total of 19 crystal structures were determined, including unprecedented structural characterization of molybdenum(0) coordination by dimethyl sulfoxide (DMSO), methanol, ethyl acetate (EtOAc), acetone, and N,N-dimethylformamide (DMF). Correlation of (13)C NMR shifts with the complex geometry suggests a direct ligand-ligand interaction between DAD and O-bonded coligands with C═O and S═O double bonds, such as EtOAc, Me(2)CO, DMF, and DMSO. Unexpectedly, the solvatochromic properties of these tricarbonyl complexes [Mo(DAD)(CO)(3)L] are unfavorable for the determination of Kamlet-Taft parameters of the corresponding solvent L. Contrastingly, the UV/vis absorption of [Mo(DAD)(CO)(4)] is strongly correlated with the Kamlet-Taft parameter π*, which is shown for 22 solvents, including seven room temperature ionic liquids.

show abstract

η ¹ σ‐Cyanide Complexes

Vallarino¹

1991

Inorganic Reactions and Methods

View full text Add to dashboard Cite

Zur Kenntnis der Chemie der Metallcarbonyle in flüssigem Ammoniak, XII. Die Reaktionen der Hexacarbonyle der Chromgruppe und ihrer Bipyridyl‐(2.2′)‐ und 1.10‐Phenanthrolin‐Substitutionsprodukte im Ammonosystem

Cited by 32 publications

References 12 publications

Three-Center M–H–B Bonds Are Strong Field Interactions. Synthesis and Characterization of M(CH₂NMe₂BH₃)₃ Complexes of Titanium, Chromium, and Cobalt

Three-Center M–H–B Bonds Are Strong Field Interactions. Synthesis and Characterization of M(CH₂NMe₂BH₃)₃ Complexes of Titanium, Chromium, and Cobalt

Molybdenum 1,4-Diazabuta-1,3-diene Tricarbonyl Solvento Complexes Revisited: From Solvatochromism to Attractive Ligand–Ligand Interaction

η ¹ σ‐Cyanide Complexes

Contact Info

Product

Resources

About

Zur Kenntnis der Chemie der Metallcarbonyle in flüssigem Ammoniak, XII. Die Reaktionen der Hexacarbonyle der Chromgruppe und ihrer Bipyridyl‐(2.2′)‐ und 1.10‐Phenanthrolin‐Substitutionsprodukte im Ammonosystem

Cited by 32 publications

References 12 publications

Three-Center M–H–B Bonds Are Strong Field Interactions. Synthesis and Characterization of M(CH2NMe2BH3)3 Complexes of Titanium, Chromium, and Cobalt

Three-Center M–H–B Bonds Are Strong Field Interactions. Synthesis and Characterization of M(CH2NMe2BH3)3 Complexes of Titanium, Chromium, and Cobalt

Molybdenum 1,4-Diazabuta-1,3-diene Tricarbonyl Solvento Complexes Revisited: From Solvatochromism to Attractive Ligand–Ligand Interaction

η 1 σ‐Cyanide Complexes

Contact Info

Product

Resources

About

Three-Center M–H–B Bonds Are Strong Field Interactions. Synthesis and Characterization of M(CH₂NMe₂BH₃)₃ Complexes of Titanium, Chromium, and Cobalt

Three-Center M–H–B Bonds Are Strong Field Interactions. Synthesis and Characterization of M(CH₂NMe₂BH₃)₃ Complexes of Titanium, Chromium, and Cobalt

η ¹ σ‐Cyanide Complexes