Reactivity of Pincer Complexes Toward Carbon Monoxide

Morales‐Morales, David

doi:10.1002/9783527621545.ch2

Cited by 5 publications

(4 citation statements)

References 50 publications

(93 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Carbonylation reactions of pincer complexes have recently been summarized . We briefly note several observations pertinent to this work with PCP pincer species.…”

Section: Resultsmentioning

confidence: 99%

Reactions of the Terminal Ni^II−OH Group in Substitution and Electrophilic Reactions with Carbon Dioxide and Other Substrates: Structural Definition of Binding Modes in an Intramolecular Ni^II···Fe^IIBridged Site

2010

View full text Add to dashboard Cite

A singular feature of the catalytic C-cluster of carbon monoxide dehydrogenase is a sulfide-bridged Ni⋯Fe locus where substrate is bound and transformed in the reversible reaction CO + H2O ⇌ CO2 + 2H+ + 2e−. A similar structure has been sought in this work. Mononuclear planar NiII complexes [Ni(pyN2Me2)L]1− (pyN2Me2 = bis(2,6-dimethylphenyl)-2,6-pyridinedicarboxamidate(2-)) derived from a NNN pincer ligand have been prepared including L = OH− (1) and CN− (7). Complex 1 reacts with ethyl formate and CO2 to form unidentate L = HCO2− (5) and HCO3− (6) products. A binucleating macrocycle was prepared which specifically binds NiII at a NNN pincer site and five-coordinate FeII at a triamine site. The NiII macrocyle forms hydroxo (14) and cyanide complexes (15) analogous to 1 and 7. Reaction of 14 with FeCl2 alone and with ethyl formate and 15 with FeCl2 affords molecules with the NiII-L-FeII bridge unit in which L = µ2:η1-OH− (17) and µ2:η2-HCO2− (18) and -CN− (19). All bridges are non-linear (17, 140.0°; 18, M-O-C 135.9° (Ni), 120.2° (Fe); 19, Ni-C-N 170.3°, Fe-N-C 141.8°) with Ni⋯Fe separations of 3.7–4.8 Å. The NiIIFeII complexes, lacking appropriate Ni-Fe-S cluster structures, are not site analogues but their synthesis and reactivity provide the first demonstration that molecular NiII…FeII sites and bridges can be attained, a necessity in the biomimetic chemistry of C-clusters.

show abstract

“…Carbonylation reactions of pincer complexes have recently been summarized . We briefly note several observations pertinent to this work with PCP pincer species.…”

Section: Resultsmentioning

confidence: 99%

Reactions of the Terminal Ni^II−OH Group in Substitution and Electrophilic Reactions with Carbon Dioxide and Other Substrates: Structural Definition of Binding Modes in an Intramolecular Ni^II···Fe^IIBridged Site

2010

View full text Add to dashboard Cite

show abstract

“…The related reaction of the aminophosphine ligand 2 with PdI 2 and with NiCl 2 (dme) led, in both cases, to the complexes (k 3 P,N, P-tBu 2 PNH(CH 2 ) 2 NPtBu 2 )MX (MX = PdI (7), NiCl (8)), respectively, whereas the reaction of 3 with PdX 2 gave (k 3 P,C, P-tBu 2 PN(Me)CHCH 2 N(Me)PtBu 2 )PdX (X = I (9), Br (10), Cl (11)). The analogous reaction of 3 with NiCl 2 (dme) afforded [(tBu 2 PH)(NMe)(CH 2 ) 2 (NMe)(tBu 2 P)NiCl 3 ], (12), which upon treatment with B(C 6 F 5 ) 3 afforded the species (k 3 P,C, P-tBu 2 PN(Me)CHCH 2 N(Me)PtBu 2 )NiCl (13). Crystallographic studies of 4À6, 8,9,11, and 12 are reported.…”

Section: ' Experimental Sectionmentioning

confidence: 99%

“…Chelating ligands have proven instrumental in the development of new catalysts; furthermore trans-chelating “pincer” ligands have garnered considerable attention over the years. − The most extensively investigated pincer complexes feature ligands based on a meta-substituted arene skeleton (PCP). Variations of the PCP-pincer framework have been shown to alter the electronic and steric properties of the corresponding metal complexes, resulting in unique reactivity. , …”

Section: Introductionmentioning

confidence: 99%

Nickel(II) and Palladium(II) Bis-Aminophosphine Pincer Complexes

Gwynne

Stephan

2011

Organometallics

View full text Add to dashboard Cite

Chelating ligands have proven instrumental in the development of new catalysts; furthermore trans-chelating "pincer" ligands have garnered considerable attention over the years. 1À13 The most extensively investigated pincer complexes feature ligands based on a meta-substituted arene skeleton (PCP). Variations of the PCP-pincer framework have been shown to alter the electronic and steric properties of the corresponding metal complexes, resulting in unique reactivity. 14,15 Aminophosphine chelating ligands of the form (linker)-(NR 0 PR 2 ) 2 have also garnered attention, as such ligands are readily prepared from diamines and chlorophosphines. 5,16 While linked diaminophosphine ligands such as (CH 2 N(R 0 )PR 2 ) 2 (R 0 = H, alkyl; R = alkyl, aryl) have been reported by Wollins, 17 Gusev, 9 Vogt, 16 and others, 18À21 investigations of PCP aminophosphine-based pincer ligand complexes have received less attention. 10 We were drawn to these systems, as such ligands offer adjacent P and N donors, suggesting the possibility of unique binding modes and thus subsequent reactivity. In this regard, the only report in which the N atom of an aminophosphine has been shown to participate in binding to a metal was recently reported by Palacios et al. In this case a bis-aminophosphine ligand was shown to bind to Ru via both P atoms as well as one of the amino NH groups, affording the Ru cation [Cp*Ru(k 3 P,N,P-(iPr 2 PNH) 2 C 6 H 10 ] + . 21 In this paper, we describe the synthesis and characterization of Ni and Pd complexes of bis-aminophosphine chelating ligands. Interestingly, these ligands are shown to readily adopt two tridentate binding modes. Participation of the secondary N adjacent to P affords k 3 P,N,P ligands that incorporate three-membered NPM metallacycles. Alternatively, metalation of the alkyl chain in the ligand backbone affords k 3 P,C,P pincer complexes.

show abstract

“…Pincer-type ligands belong to a family of tridentate ligands where the central anionic or neutral donor site is flanked by two neighboring donor groups (Y = C, N, Si; D is a neutral two-electron donor, see Figure ). Their DYD η 3 -mer coordination to transition or main group metals gives rise to the formation of Y-M bond-sharing bicyclic structures , that are often translated into robust materials featuring exceptional thermodynamic stability. , On the other hand, structural modification of the coordinating environment helps to control reactivity of the complexes by controlling steric, as well as, electronic properties of the metal center. − Combination of these factors placed these fascinating compounds in a domain of very intensive research activity and eventually made them very popular in many branches of catalysis, − basic organometallic and coordination chemistry. − Moreover, pincer complexes are rapidly entering the areas traditionally occupied by inorganic or organic materials such as design of high-performance materials, − bioinorganic , and supramolecular chemistry. − …”

Section: Introductionmentioning

confidence: 99%

Coordination Versatility of sp³-Hybridized Pincer Ligands toward Ligand–Metal Cooperative Catalysis

2012

View full text Add to dashboard Cite

Pincer-type complexes occupy a very important position in chemistry and chemistry-related disciplines. In this article we have selected several spectacular examples of pincer systems and demonstrate that reversible structural changes in the ligand backbone may have a dramatic impact on the reactivity of their metal complexes. This perspective aims to focus on some recent exciting developments in the chemistry of "cooperating" PN(sp 3 )P and PC(sp 3 )P pincer ligands relevant to catalytic applications.

show abstract

Reactivity of Pincer Complexes Toward Carbon Monoxide

Cited by 5 publications

References 50 publications

Reactions of the Terminal Ni^II−OH Group in Substitution and Electrophilic Reactions with Carbon Dioxide and Other Substrates: Structural Definition of Binding Modes in an Intramolecular Ni^II···Fe^IIBridged Site

Reactions of the Terminal Ni^II−OH Group in Substitution and Electrophilic Reactions with Carbon Dioxide and Other Substrates: Structural Definition of Binding Modes in an Intramolecular Ni^II···Fe^IIBridged Site

Nickel(II) and Palladium(II) Bis-Aminophosphine Pincer Complexes

Coordination Versatility of sp³-Hybridized Pincer Ligands toward Ligand–Metal Cooperative Catalysis

Contact Info

Product

Resources

About

Reactivity of Pincer Complexes Toward Carbon Monoxide

Cited by 5 publications

References 50 publications

Reactions of the Terminal NiII−OH Group in Substitution and Electrophilic Reactions with Carbon Dioxide and Other Substrates: Structural Definition of Binding Modes in an Intramolecular NiII···FeIIBridged Site

Reactions of the Terminal NiII−OH Group in Substitution and Electrophilic Reactions with Carbon Dioxide and Other Substrates: Structural Definition of Binding Modes in an Intramolecular NiII···FeIIBridged Site

Nickel(II) and Palladium(II) Bis-Aminophosphine Pincer Complexes

Coordination Versatility of sp3-Hybridized Pincer Ligands toward Ligand–Metal Cooperative Catalysis

Contact Info

Product

Resources

About

Reactions of the Terminal Ni^II−OH Group in Substitution and Electrophilic Reactions with Carbon Dioxide and Other Substrates: Structural Definition of Binding Modes in an Intramolecular Ni^II···Fe^IIBridged Site

Reactions of the Terminal Ni^II−OH Group in Substitution and Electrophilic Reactions with Carbon Dioxide and Other Substrates: Structural Definition of Binding Modes in an Intramolecular Ni^II···Fe^IIBridged Site

Coordination Versatility of sp³-Hybridized Pincer Ligands toward Ligand–Metal Cooperative Catalysis