Bifunctional Hydroboration Catalyst Activation Using a Co SNS Amido Complex Bearing an Abnormal-NHC Ligand DOI
Saeed Ataie,

Atousa Khanzadeh,

Loïc P. Mangin

et al.

Organometallics, Journal Year: 2023, Volume and Issue: 43(18), P. 1956 - 1963

Published: Oct. 27, 2023

In previous work, different supporting L-type ligands were incorporated in Fe(II) SNS pincer catalysts by monoprotonation of the bis(amido) complex, mer-[Fe(κ3-SMeNSMe)2] (Fe-1), affording isolable Fe amido-amine cation with an easily displaced amine ligand. Herein we show that protonation Co analogue (Co-1) proceeds directly to bis(amine) dication, fac-[Co(κ3-SMeNHSMe)2]2+. DFT studies clearly corroborate mer → fac isomerization upon diprotonation both and complexes. To access ancillary ligated hydroboration precatalyst, treatment Co-1 1,3-bis(1-adamantyl)imidazolium chloride (IAd·HCl) effects amido ligand addition, yielding abnormally coordinated (at C4 instead C2) IAd CoIICl(κ2-SMeNSMe)(a-IAd) (Co-3). calculations showed Co-3 is only slightly more stable than normal isomer, suggesting a role for kinetic control due steric factors. Stoichiometric pinacolborane (HBpin) afforded free N-borylamine but served as effective carbonyl catalyst, showing important a-IAd stabilizing cobalt throughout catalytic cycle.

Language: Английский

Secondary-sphere preorganization enables nickel-catalyzed nitrile hydroboration DOI
Medina Afandiyeva, Xijue Wu, William W. Brennessel

et al.

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(90), P. 13450 - 13453

Published: Jan. 1, 2023

Herein, we describe nickel-catalyzed nitrile hydroboration with pinacolborane, wherein a tethered NHC-pyridonate ligand enables efficient catalysis (5 mol% [Ni], ≤6 h reaction time) at room temperature. Mechanistic studies, including isolation of the catalytically relevant intermediates, shed light on cooperative role in activating both reagents simultaneously.

Language: Английский

Citations

10
Synthesis, Characterization and Application of NNN Pincer Manganese Complexes with Pyrazole Framework in α-Alkylation Reaction DOI Creative Commons
Tao Wang, Yongli Xu,

Mengxin Du

et al.

Molecules, Journal Year: 2025, Volume and Issue: 30(7), P. 1465 - 1465

Published: March 26, 2025

A series of novel NNN pincer manganese complexes based on pyrazole skeleton 4 were efficiently synthesized in a two-step process. All the new fully characterized by 1H, 13C NMR spectra. Furthermore, molecular structures 4a and 4c also determined X-ray single-crystal diffraction. The manganese(I) catalysts obtained showed efficient catalytic activity α-alkylation reaction ketones with alcohols. Under optimal conditions, expected products procured moderate to high yields.

Language: Английский

Citations

0
NNN pincer palladium(II) complexes with N-(2-(1H-pyrazol-1-yl)phenyl)-picolinamide ligands: synthesis, characterization, and application to heck coupling reaction DOI
Yongli Xu, Tao Wang,

Yong-Hua Li

et al.

Transition Metal Chemistry, Journal Year: 2024, Volume and Issue: 49(3), P. 149 - 159

Published: Jan. 28, 2024

Language: Английский

Citations

3
Bifunctional Activation of NHC‐Zinc Pre‐Catalyst for Effective Hydroboration of Quinolines and Nitriles DOI Open Access
Saeed Ataie, R. Tom Baker

ChemCatChem, Journal Year: 2023, Volume and Issue: 15(20)

Published: July 17, 2023

Abstract Zinc dihydride complexes supported by bulky N‐heterocyclic carbenes (NHC) are efficient catalysts in hydroboration reactions. Herein, a set of zinc with an amino‐pyrrolide chelate (H L 1 ) and the small NHC ligand, 2,3‐dimethyl‐3,4‐dichloroimidazol‐2‐ylidene (DDI) was synthesized characterized. In particular, Zn(H 2 ( Zn4) displayed high activity catalytic nitrile dihydroboration using 0.01 mol % loading, quinoline 0.05 loading at room temperature. Stoichiometric reaction Zn4 4 equiv. pinacolborane (HBpin) produced ZnH Zn5 dissociated (Bpin) . Complex , generated situ this bifunctional catalyst activation step, shown to be more active than bis‐NHC analog previously reported examples ligands. addition, variable time normalization analysis (VTNA) showed first‐order dependence on [quinoline], [HBpin] [ ], revealing that single Zn−H is involved cycle, as also observed stoichiometric quinoline. VTNA indicated faces neither deactivation nor product inhibition.

Language: Английский

Citations

6
Reactions of nickel boranyl compounds with pnictogen–carbon triple bonds DOI Creative Commons
Brady J. H. Austen, Marissa L. Clapson, Marcus W. Drover

et al.

RSC Advances, Journal Year: 2023, Volume and Issue: 13(28), P. 19158 - 19163

Published: Jan. 1, 2023

The catalytic conversion of unsaturated small molecules such as nitriles into reduced products is interest for the production fine chemicals. In this vein, metal-ligand cooperativity has been leveraged to promote reactivity, often conferring stability bound substrate - a balancing act that may offer activation at cost turnover efficiency. This report describes reactivity [(diphosphine)Ni] compound with pnictogen carbon triple bonds (R-C[triple bond, length m-dash]E; E = N, P), where diphosphine contains two pendant borane groups. For cooperative nitrile coordination observed afford {Ni}2 complexes displaying B-N interactions, whereas P, B-P interactions are absent. work additionally outlines structure-activity relationship uses dihydroboration model reaction unveil effect SCS stabilization, employing 0, 1, or 2 Lewis acid

Language: Английский

Citations

5
Selective Cobalt(II)–SNS Dithiolate Complex-Catalyzed Bifunctional Hydroboration of Aldehydes: Kinetics and Mechanistic Studies DOI
Saeed Ataie, Samantha L. Dudra, Erin R. Johnson

et al.

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(15), P. 10076 - 10084

Published: July 18, 2023

Anionic ligands containing a nonbonded lone pair (i.e., amido, thiolate) are well-known to cooperate with metal center in bifunctional catalytic reactions. An NHC CoII(κ3-SNS) imine–dithiolate complex (Co-3) effects the selective hydroboration of aldehydes (vs ketones) 4–30 min at 1 mol % loading benzene (NHC = 2,5-dimethyl-3,4-dichloroimidazol-2-ylidene). Although catalyst was unchanged stoichiometric reactions aldehyde or borane, VTNA kinetic studies showed first-order rate dependence on concentrations Co-3, aldehyde, and pinacolborane as well significant product inhibition. DFT confirmed transition state B–H activation 5-membered ring thiolate donor being slightly favored over 6-membered ring. Stable van der Waals complexes Co-3 both benzaldehyde its were also identified, reuse further inhibition, especially aromatic aldehydes. Reactivation easily accomplished by removal using hexane.

Language: Английский

Citations

5
Zinc Hydride-Catalyzed Dihydroboration of Isonitriles and Nitriles: Mechanistic Studies with the Structurally Characterized Zinc Intermediates DOI
Rajata Kumar Sahoo, Sagrika Rajput,

Sneha Dutta

et al.

Organometallics, Journal Year: 2023, Volume and Issue: 42(16), P. 2293 - 2303

Published: Aug. 16, 2023

The conjugated bis-guanidinate (CBG)-stabilized zinc hydride, [{LZnH}2; (L = {(ArNH)(ArN)–C═N–C═(NAr)(NHAr)}; Ar 2,6-Et2-C6H3)] (Zn-1), is shown to be a highly active catalyst for the double reduction of isonitriles and nitriles with pinacolborane (HBpin) in this study. A wide array nitriles, including aryl alkyl groups, underwent hydroboration afford exclusively 1,2- 1,1-diborylated amine products, respectively. series stoichiometric reactions were performed understand reaction mechanisms. Hydroboration isonitrile proceeds through formation formimidoyl complex, [LZnC(H)N(tBu)]2 (Zn-2), while nitrile vinylidenamido [LZnNC(H)(C6H5)]2 (Zn-3). Moreover, compounds Zn-2 Zn-3 are isolated thoroughly characterized. Such molecular complexes rare literature.

Language: Английский

Citations

5
Iron complexes supported by silyl-NHC chelate ligands: synthesis and use for double hydroboration of nitriles DOI
Takashi Komuro,

Kohei Hayasaka,

Kasumi Takahashi

et al.

Dalton Transactions, Journal Year: 2024, Volume and Issue: 53(9), P. 4041 - 4047

Published: Jan. 1, 2024

Iron complexes with newly designed silyl-NHC bidentate ligands showed high performance in the catalytic double hydroboration of nitriles to produce N , -bis(boryl)amines.

Language: Английский

Citations

1
Tetracopper(i) thiolate- and amido-(SNS) complexes and copper-catalyzed azide–alkyne cycloaddition in water DOI

Atousa Khanzadeh,

Saeed Ataie, R. Tom Baker

et al.

Dalton Transactions, Journal Year: 2023, Volume and Issue: 52(34), P. 11768 - 11772

Published: Jan. 1, 2023

A tetranuclear Cu(I) complex bearing thiolate-SNS ligands catalyzes the azide-alkyne cyclization in water at 70 °C.

Language: Английский

Citations

3
Magnesium(Ⅱ) complexes supported by indole- and pyrrole-containing Schiff-base ligands: syntheses, structures, and applications as precatalysts in the hydroboration of nitriles and alkynes DOI

Meng‐Xiang Wu,

Ling Chen, Xiaohan Yang

et al.

New Journal of Chemistry, Journal Year: 2024, Volume and Issue: 48(16), P. 7125 - 7133

Published: Jan. 1, 2024

Five magnesium compounds were synthesized. They are active precatalysts for the hydroboration of nitriles and alkynes. The catalytic reactions feature mild reaction conditions, excellent functional group tolerance, high yields.

Language: Английский

Citations

0