2,6-Lutidine-linked bis-saturated NHC pincer ligands, silver complexes and transmetallation

Asay, Matthew; Quezada-Miriel, Magdalena; Ochoa-Sanfelice, J. Rubén; Martı́nez-Otero, Diego

doi:10.1016/j.jorganchem.2018.01.044

Cited by 10 publications

(7 citation statements)

References 59 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the same line, reaction of salts 1 and 2 with basic methoxo-bridged complexes [{Rh(μ-OMe)(olef)} 2 ], which were expected to deprotonate the NC(H)N fragments of the pincer ligands, did not work either. Transmetalation protocol by using silver NHC derivatives was also unsuccessful …”

Section: Resultsmentioning

confidence: 99%

Rh Complexes with Pincer Carbene CNC Lutidine-Based Ligands: Reactivity Studies toward H₂Addition

et al. 2021

View full text Add to dashboard Cite

Lutidine-based NHCs pincer precursors CNC Me and CNC Mes were combined with [Rh(acac)(nbd)] (acac = acetylacetonate; nbd = 2,5-norbornadiene) in the presence of Cs2CO3 to yield complexes [(CNC) Me Rh(nbd)]PF6 (3) and [(CNC) Mes Rh(NCMe)]PF6 (4), respectively. While in 3, the nbd diolefin remains coordinated, in 4, the voluminous mesityl ligands induce nbd decoordination, so acetonitrile stabilizes Rh(I) adduct 4, which in turn undergoes substitution reactions with a number of neutral ligands to produce cationic complexes [(CNC) Mes Rh(L)]PF6 (L = CO (5), PMe2Ph (6), PEt3 (7), C2H4 (8)). These complexes have been studied through VT NMR measurements and the molecular structures by X-ray crystallography in the case of adducts 4–7. Deprotonation reactions on cationic complexes 3–6 with hard bases yielded the corresponding neutral complexes [(CNC)* Me Rh(nbd)] (9) and mesityl derivatives [(CNC)* Mes Rh(L)] (L = NCCH3 (10), CO (11), PMe2Ph (12)), all of which are dearomatized complexes due to the deprotonation of one of the methylene arms, a situation confirmed by the X-ray molecular structure of carbonyl adduct 5. We studied the reactivity toward dihydrogen with neutral adducts 11 and 12. The electron rich phosphane 12 adds H2 through oxidative addition, affording the bis(hydrido) Rh(III) complex [(CNC)* Mes Rh(PMe2Ph)H2] (14). However, the carbonyl adduct 11 reacts with H2 in a different way, so that the central pyridinic ring becomes hydrogenated, breaking the aromaticity and leading to complex [(CNC-H2)* Mes Rh(CO)] (13), isolated as a mixture of two isomers. DFT studies were carried out in order to establish the mechanisms followed on these hydrogenations, finding that, while the phosphane adduct reacts following an oxidative addition mechanism, the carbonyl complex follows a more complex base-induced profile due to the instability of hydride carbonyl species.

show abstract

Section: Resultsmentioning

confidence: 99%

Rh Complexes with Pincer Carbene CNC Lutidine-Based Ligands: Reactivity Studies toward H₂Addition

et al. 2021

View full text Add to dashboard Cite

show abstract

“…In this respect, Asay's group has accessed two Ni II pincer complexes 15 a/b bearing imidazolidin‐2‐ylidenes (Scheme 7). [17] This ligand platform is a good addition to the known pincer ligands, although no further applications were demonstrated in this work.…”

Section: Nhc Employed As An Arm Donormentioning

confidence: 91%

Transition Metal Complexes Supported by N‐Heterocyclic Carbene‐Based Pincer Platforms: Synthesis, Reactivity and Applications

2020

View full text Add to dashboard Cite

show abstract

“…Recently, we and others have been interested in the synthesis and reactivity of MOFs constructed from pincer complexes. − In particular, diphosphine pincer ligands have become ubiquitous in homogeneous catalysis owing to their versatility and ability to support a wide range of late transition metals. − The combination of the chelating pincer framework and strong phosphine donor groups confers a high degree of stability that makes the pincer complexes resistant to demetalation and often allows them to withstand high temperatures and harsh catalytic conditions. Consequently, reported examples of metal exchange reactions with pincer ligand scaffolds are rare and have been limited to a few Zr and Ag complexes. − To the best of our knowledge, there are no reported examples of transition metal exchange reactions with diphosphine pincer complexes. Herein we report the direct solvothermal synthesis of a Zr MOF, 1-CoCl 3 , constructed from Co III -P N N N P pincer metallolinkers.…”

Section: Introductionmentioning

confidence: 99%

Postsynthetic Metal Exchange in a Metal–Organic Framework Assembled from Co(III) Diphosphine Pincer Complexes

et al. 2019

View full text Add to dashboard Cite

A Zr metal–organic framework (MOF) 1-CoCl3 has been synthesized by solvothermal reaction of ZrCl4 with a carboxylic acid-functionalized CoIII-PNNNP pincer complex H4(L-CoCl3) ([L-CoCl3]4– = [(2,6-(NHPAr2)2C6H3)CoCl3]4–, Ar = p-C6H4CO2 –). The structure of 1-CoCl3 has been determined by X-ray powder diffraction and exhibits a csq topology that differs from previously reported ftw-net Zr MOFs assembled from related PdII- and PtII-PNNNP pincer complexes. The Co-PNNNP pincer species readily demetallate upon reduction of CoIII to CoII, allowing for transmetalation with late second and third row transition metals in both the homogeneous complex and 1-CoCl3 . Reaction of 1-CoCl3 with [Rh(nbd)Cl]2 (nbd = 2,5-nobornadiene) results in complete Rh/Co metal exchange at the supported diphosphine pincer complexes to generate 1-RhCl, which has been inaccessible by direct solvothermal synthesis. Treating 1-CoCl3 with PtCl2(SMe2)2 in the presence of the mild reductant NEt3 resulted in nearly complete Co substitution by Pt. In addition, a mixed metal pincer MOF, 1-PtRh, was generated by sequential substitution of Co with Pt followed by Rh.

show abstract

2,6-Lutidine-linked bis-saturated NHC pincer ligands, silver complexes and transmetallation

Cited by 10 publications

References 59 publications

Rh Complexes with Pincer Carbene CNC Lutidine-Based Ligands: Reactivity Studies toward H₂Addition

Rh Complexes with Pincer Carbene CNC Lutidine-Based Ligands: Reactivity Studies toward H₂Addition

Transition Metal Complexes Supported by N‐Heterocyclic Carbene‐Based Pincer Platforms: Synthesis, Reactivity and Applications

Postsynthetic Metal Exchange in a Metal–Organic Framework Assembled from Co(III) Diphosphine Pincer Complexes

Contact Info

Product

Resources

About

2,6-Lutidine-linked bis-saturated NHC pincer ligands, silver complexes and transmetallation

Cited by 10 publications

References 59 publications

Rh Complexes with Pincer Carbene CNC Lutidine-Based Ligands: Reactivity Studies toward H2Addition

Rh Complexes with Pincer Carbene CNC Lutidine-Based Ligands: Reactivity Studies toward H2Addition

Transition Metal Complexes Supported by N‐Heterocyclic Carbene‐Based Pincer Platforms: Synthesis, Reactivity and Applications

Postsynthetic Metal Exchange in a Metal–Organic Framework Assembled from Co(III) Diphosphine Pincer Complexes

Contact Info

Product

Resources

About

Rh Complexes with Pincer Carbene CNC Lutidine-Based Ligands: Reactivity Studies toward H₂Addition

Rh Complexes with Pincer Carbene CNC Lutidine-Based Ligands: Reactivity Studies toward H₂Addition