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24 Mar 10:56

Alkali‐Metal‐Alkoxide Powered Zincation of Fluoroarenes Employing Zinc Bis‐Amide Zn(TMP)2

by Neil Judge, Eva Hevia

Reminiscent of Lochmann-Schlosser superbase recipes, the addition of two molar equivalents of KOtBu to Zn(TMP)2(TMP = 2,2,6,6-tetramethylpiperidide) transforms this mild zinc bis-amide base to a powerful metalating agent able to perform facile regioselective zincation of a wide range of sensitive fluoroarenes. Structural authentication of the intermediates post Zn-H exchange demonstrates activation of both TMP groups to form a range of higher order bis-aryl potassium zincates, isolable as solids and further functionalized in electrophilic interception reactions. Studies assessing the role of KOtBu reveal that the first equivalent undergoes co-complexation with Zn(TMP)2, enabling kinetic activation of the amide groups; whereas the second equivalent stabilizes the metalated intermediate preventing ligand redistribution. Showcasing its metalating power, this bimetallic KOtBu/Zn(TMP)2 partnership, can effect  zincation of toluene and benzene at room temperature.

09 Mar 12:54

[ASAP] Li vs Na: Divergent Reaction Patterns between Organolithium and Organosodium Complexes and Ligand-Catalyzed Ketone/Aldehyde Methylenation

by Nathan Davison, Claire L. McMullin, Lu Zhang, Shu-Xian Hu, Paul G. Waddell, Corinne Wills, Casey Dixon, and Erli Lu

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Journal of the American Chemical Society
DOI: 10.1021/jacs.3c01033
03 Mar 11:40

Cooperative dihydrogen activation at a Na(I)2/Mg(I)2 ensemble

Chem. Commun., 2023, 59,3846-3849
DOI: 10.1039/D3CC00710C, Communication
Open Access Open Access
Creative Commons Licence&nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Han-Ying Liu, Samuel E. Neale, Michael S. Hill, Mary F. Mahon, Claire L. McMullin, Benjamin L. Morrison
[{SiNDipp}MgNa]2 ({SiNDipp} = {CH2SiMe2N(Dipp)}2; Dipp = 2,6-i-Pr2C6H3) reacts directly with H2 in a process, which computational studies suggest, is dictated by the frontier MOs of both H2 and the low oxidation state s-block assembly.
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15 Feb 11:55

Structural snapshots of an Al–Cu bond-mediated transformation of terminal acetylenes

Chem. Sci., 2023, 14,2866-2876
DOI: 10.1039/D3SC00240C, Edge Article
Open Access Open Access
Creative Commons Licence&nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Han-Ying Liu, Samuel E. Neale, Michael S. Hill, Mary F. Mahon, Claire L. McMullin
The C–Al bond of [{SiNDipp}Al–Cu(NHCiPr)] reacts sequentially with three equivalents of terminal alkyne to provide cuprous (hydrido)(alkynyl)aluminate, (E-alkenyl)(alkynyl)aluminate and bis(alkynyl)aluminate derivatives.
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02 Feb 08:53

Metal‐Mediated Oligomerization Reactions of the Cyaphide Anion

by Eric S. Yang, Daniel W. N. Wilson, Jose M. Goicoechea
Metal-Mediated Oligomerization Reactions of the Cyaphide Anion

We describe three distinct oligomerization reactions of metal complexes bonded to the cyaphide ligand (CP). Reductive coupling of a gold cyaphido complex was found to afford a species containing a C2P2 4− dimer. By contrast, sterically unprotected metal complexes with more polar M−CP (M=Ni, Sc) bonds were found to spontaneously oligomerize giving rise to species with bridging C2P2 2− and C3P3 3− ligands.


Abstract

The cyaphide anion, CP, is shown to undergo three distinct oligomerization reactions in the coordination sphere of metals. Reductive coupling of Au(IDipp)(CP) (IDipp=1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) by Sm(Cp*)2(OEt2) (Cp*=1,2,3,4,5-pentamethylcyclopentadienyl), was found to afford a tetra-metallic complex containing a 2,3-diphosphabutadiene-1,1,4,4-tetraide fragment. By contrast, non-reductive dimerization of Ni(SIDipp)(Cp)(CP) (SIDipp=1,3-bis(2,6-diisopropylphenyl)-imidazolidin-2-ylidene; Cp=cyclopentadienyl), gives rise to an asymmetric bimetallic complex containing a 1,3-diphosphacyclobutadiene-2,4-diide moiety. Spontaneous trimerization of Sc(Cp*)2(CP) results in the formation of a trimetallic complex containing a 1,3,5-triphosphabenzene-2,4,6-triide fragment. These transformations show that while cyaphido transition metal complexes can be readily accessed using metathesis reactions, many such species are unstable to further oligomerization processes.

30 Jan 12:57

[ASAP] An Illustrated Guide to Schlenk Line Techniques

by Andryj M. Borys

TOC Graphic

Organometallics
DOI: 10.1021/acs.organomet.2c00535
24 Jan 08:50

[ASAP] Mechanistic Insights into Molecular Crystalline Organometallic Heterogeneous Catalysis through Parahydrogen-Based Nuclear Magnetic Resonance Studies

by Matthew R. Gyton, Cameron G. Royle, Simon K. Beaumont, Simon B. Duckett, and Andrew S. Weller

TOC Graphic

Journal of the American Chemical Society
DOI: 10.1021/jacs.2c12642
11 Jan 12:34

Frustrated Lewis Pair Adduct of Atomic P(−1) as a Source of Phosphinidenes (PR), Diphosphorus (P2), and Indium Phosphide

by Brandon L Frenette, Jonathan Trach, Michael J. Ferguson, Eric Rivard
Frustrated Lewis Pair Adduct of Atomic P(−1) as a Source of Phosphinidenes (PR), Diphosphorus (P2), and Indium Phosphide

A frustrated Lewis pair (FLP) chelation approach was employed to access low-valent phosphorus centers. The resulting adducts act as P atom sources for phosphinidene (PR) transfer, indium phosphide synthesis, and neutral P2 transfer to organic substrates.


Abstract

We report phosphinidenes (PR) stabilized by an intramolecular frustrated Lewis pair (FLP) chelate. These adducts include the parent phosphinidene, PH, which is accessed via thermolysis of coordinated HPCO. The reported FLP-PH species acts as a springboard to other phosphorus-containing compounds, such as FLP-adducts of diphosphorus (P2) and InP3. Our new adducts participate in thermal- or light-induced phosphinidene elimination (of both PH and PR, R=organic group), transfer P2 units to an organic substrate, and yield the useful semiconductor InP at only 110 °C from solution.

11 Jan 08:43

Diphenylacetylene stabilised alkali-metal nickelates: synthesis, structure and catalytic applications

Dalton Trans., 2023, 52,2098-2105
DOI: 10.1039/D3DT00069A, Paper
Open Access Open Access
Andryj M. Borys, Eva Hevia
Using diphenylacetylene as a π-accepting ligand allows access to a new family of alkali-metal nickelates, which can effectively promote the [2 + 2 + 2] cyclotrimerisation of diphenylacetylene.
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06 Jan 09:21

Beryllium-centred C–H activation of benzene

Chem. Commun., 2023, 59,1453-1456
DOI: 10.1039/D2CC06702A, Communication
Open Access Open Access
Creative Commons Licence&nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Kyle G. Pearce, Michael S. Hill, Mary F. Mahon
Lithium or sodium reduction of [SiNDippBe] in benzene, provides the organoberyllate products, [{SiNDippBePh}M] (M = Li or Na).
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04 Jan 10:24

The emerging chemistry of the aluminyl anion

Chem. Commun., 2023, 59,503-519
DOI: 10.1039/D2CC05963K, Feature Article
Martyn P. Coles, Matthew J. Evans
The chemistry of aluminyl compounds has rapidly expanded since their discovery in 2018 and is evaluated in this summary.
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19 Dec 13:21

[ASAP] A Free Phosphaborene Stable at Room Temperature

by Jiancheng Li, Zhihao Lu, and Liu Leo Liu

TOC Graphic

Journal of the American Chemical Society
DOI: 10.1021/jacs.2c11878
06 Dec 08:56

[ASAP] Al–Sc Bonded Complexes: Synthesis, Structure, and Reaction with Benzene in the Presence of Alkyl Halide

by Genfeng Feng, Ka Lok Chan, Zhenyang Lin, and Makoto Yamashita

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Journal of the American Chemical Society
DOI: 10.1021/jacs.2c09746
27 Nov 13:52

Alkaline‐Earth Metal Mediated Benzene‐to‐Biphenyl Coupling

by Jonathan Mai, Michael Morasch, Dawid Jędrzkiewicz, Jens Langer, Bastian Rösch, Sjoerd Harder
Alkaline-Earth Metal Mediated Benzene-to-Biphenyl Coupling

Attempts to isolate low-valent (BDI)Ae-Ae(BDI) complexes led to reduction of the benzene solvent and formation of (BDI)Ae-(C6H6)-Ae(BDI); BDI=β-diketiminate ligand, Ae=Ca or Sr. Reaction of bridging C6H6 2− with benzene gave (biphenyl)2− complexes. Ball-milling is an efficient synthetic tool for this dehydrogenative benzene-benzene coupling. Calculations suggest attack of C6H6 2− at benzene. This is facilitated by Ae2+⋅⋅⋅benzene coordination.


Abstract

Complex [(DIPePBDI)Ca]2(C6H6), with a C6H6 2− dianion bridging two Ca2+ ions, reacts with benzene to yield [(DIPePBDI)Ca]2(biphenyl) with a bridging biphenyl2− dianion (DIPePBDI=HC[C(Me)N-DIPeP]2; DIPeP=2,6-CH(Et)2-phenyl). The biphenyl complex was also prepared by reacting [(DIPePBDI)Ca]2(C6H6) with biphenyl or by reduction of [(DIPePBDI)CaI]2 with KC8 in presence of biphenyl. Benzene-benzene coupling was also observed when the deep purple product of ball-milling [(DIPPBDI)CaI(THF)]2 with K/KI was extracted with benzene (DIPP=2,6-CH(Me)2-phenyl) giving crystalline [(DIPPBDI)Ca(THF)]2(biphenyl) (52 % yield). Reduction of [(DIPePBDI)SrI]2 with KC8 gave highly labile [(DIPePBDI)Sr]2(C6H6) as a black powder (61 % yield) which reacts rapidly and selectively with benzene to [(DIPePBDI)Sr]2(biphenyl). DFT calculations show that the most likely route for biphenyl formation is a pathway in which the C6H6 2− dianion attacks neutral benzene. This is facilitated by metal-benzene coordination.

24 Nov 09:01

[ASAP] Synthesis, Characterization, and Structural Analysis of AM[Al(NONDipp)(H)(SiH2Ph)] (AM = Li, Na, K, Rb, Cs) Compounds, Made Via Oxidative Addition of Phenylsilane to Alkali Metal Aluminyls

by Gerd M. Ballmann, Matthew J. Evans, Thomas X. Gentner, Alan R. Kennedy, J. Robin Fulton, Martyn P. Coles, and Robert E. Mulvey

TOC Graphic

Inorganic Chemistry
DOI: 10.1021/acs.inorgchem.2c03010
18 Nov 08:59

Reduction of Na+ within a {Mg2Na2} Assembly

by Han-Ying Liu, Samuel E. Neale, Michael Stephen Hill, Mary F. Mahon, Claire L McMullin, Emma Richards
Reduction of Na+ within a {Mg2Na2} Assembly

Treatment of a low oxidation state {Mg2Na2} assembly with basic molecules that are less prone to reduction than the sodium cation itself induces the complete extrusion of the elemental alkali metal.


Abstract

Ionic compounds containing sodium cations are notable for their stability and resistance to redox reactivity unless highly reducing electrical potentials are applied. Here we report that treatment of a low oxidation state {Mg2Na2} species with non-reducible organic bases induces the spontaneous and completely selective extrusion of sodium metal and oxidation of the MgI centers to the more conventional MgII state. Although these processes are also characterized by a structural reorganisation of the initially chelated diamide spectator ligand, computational quantum chemical studies indicate that intramolecular electron transfer is abetted by the frontier molecular orbitals (HOMO/LUMO) of the {Mg2Na2} ensemble, which arise exclusively from the 3s valence atomic orbitals of the constituent sodium and magnesium atoms.

08 Nov 13:53

Anionic Magnesium and Calcium Hydrides: Transforming CO into Unsaturated Disilyl Ethers

by Jacob S. McMullen, Ryan Huo, Petra Vasko, Alison J. Edwards, Jamie Hicks
Anionic Magnesium and Calcium Hydrides: Transforming CO into Unsaturated Disilyl Ethers

CO has directly been transformed into small organic starting materials using earth-abundant, anionic group 2 hydride reagents.


Abstract

The synthesis, characterisation and reactivity of two isostructural anionic magnesium and calcium complexes is reported. By X-ray and neutron diffraction techniques, the anionic hydrides are shown to exist as dimers, held together by a range of interactions between the two anions and two bridging potassium cations. Unlike the vast proportion of previously reported dimeric group 2 hydrides, which have hydrides that bridge two group 2 centres, here the hydrides are shown to be “terminal”, but stabilised by interactions with the potassium cations. Both anionic hydrides were found to insert and couple CO under mild reaction conditions to give the corresponding group 2 cis-ethenediolate complexes. These cis-ethenediolate complexes were found to undergo salt elimination reactions with silyl chlorides, allowing access to small unsaturated disilyl ethers with a high percentage of their mass originating from the C1 source CO.

04 Nov 08:52

Triple dehydrofluorination as a route to amidine-functionalized, aromatic phosphorus heterocycles

Chem. Commun., 2022, 58,13580-13583
DOI: 10.1039/D2CC05178H, Communication
Open Access Open Access
Nathan T. Coles, Lucie J. Groth, Lea Dettling, Daniel S. Frost, Massimo Rigo, Samuel E. Neale, Christian Müller
Hitherto unknown amidine-functionalized phosphabenzenes selectively form by a cascade of dehydrofluorination reactions.
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31 Oct 10:56

[ASAP] Perdeuteration of Arenes via Hydrogen Isotope Exchange Catalyzed by the Superbasic Sodium Amide Donor Species NaTMP·PMDETA

by Andreu Tortajada and Eva Hevia

TOC Graphic

Journal of the American Chemical Society
DOI: 10.1021/jacs.2c09778
08 Apr 08:05

(PNSiMe3)4(NMe)6: A Robust Tetravalent Phosphaza‐adamantane Scaffold for Molecular and Macromolecular Construction

by Joseph Bedard, Nicholas Roberts, Mohsen Shayan, Karlee L Bamford, Ulrike Werner-Zwanziger, Katherine M. Marczenko, Saurabh S. Chitnis
(PNSiMe3)4(NMe)6: A Robust Tetravalent Phosphaza-adamantane Scaffold for Molecular and Macromolecular Construction**

The synthesis of a new air-stable and thermally robust tetrahedral tetravalent inorganic cage, (PNSiMe3)4(NMe)6 has been achieved. This cage allows four-fold functionalization reactions on its periphery to give unprecedented molecular and macromolecular constructs. This utility is shown by the synthesis of a tetrakis(bis(phosphine)iminium) ion and the first all P/N polyphazene network material.


Abstract

Tetraarylmethanes and adamantanes are important rigid covalent connectors that play a four-way scaffolding role in molecular and materials chemistry. We report the synthesis of a new tetravalent phosphaza-adamantane cage, (PNSiMe3)4(NMe)6 (2), that shows high thermal, air, and redox stability due to its geometry. It nevertheless participates in covalent four-fold functionalization reactions along its periphery. The combination of a robust core and reactive corona makes 2 a convenient inorganic scaffold upon which tetrahedral molecular and macromolecular chemistry can be constructed. This potential is demonstrated by the synthesis of a tetrakis(bis(phosphine)iminium) ion (in compound 3) and the first all P/N poly(phosphazene) network (5).

28 Mar 07:56

A Terphenyl Supported Dioxophosphorane Dimer: the Light Congener of Lawesson's and Woollins’ Reagents

by Laura E English, Aleksandra Pajak, Claire L McMullin, John P Lowe, Mary F Mahon, David Liptrot
A Terphenyl Supported Dioxophosphorane Dimer: the Light Congener of Lawesson's and Woollins’ Reagents

Pyridines have been shown to mediate the release of ethene from a terphenyl supported 1,3-dioxo-2-phospholane. This generates a dioxophosphorane dimer which is an oxygen analogue of Lawesson's and Woollins’ reagents. This compound was structurally characterised and its solution behaviour interrogated. Insight into the ethene release reaction is provided by the isolation of a DMAP-coordinated dioxophosphorane


Abstract

Thermolysis of a 1,3-dioxa-2-phospholane supported by the terphenyl ligand AriPr4 (AriPr4=[C6H3-2,6-(C6H3-2,6-iPr2)]) at 150 °C gives [AriPr4PO2]2 via loss of ethene. [AriPr4PO2]2 was characterised by X-ray crystallography and NMR spectroscopy; it contains a 4-membered P−O−P−O ring and is the isostructural oxygen analogue of Lawesson's and Woollins’ reagents. The dimeric structure of [AriPr4PO2]2 was found to persist in solution through VT NMR spectroscopy and DOSY, supported by DFT calculations. The addition of DMAP to the 1,3-dioxa-2-phospholane facilitates the loss of ethene to give AriPr4(DMAP)PO2 after days at room temperature, with this product also characterised by X-ray crystallography and NMR spectroscopy. Replacement of the DMAP with pyridine induces ethene loss from the 1,3-dioxa-2-phospholane to provide gram-scale samples of [AriPr4PO2]2 in 75 % yield in 2 days at only 100 °C.

25 Feb 11:01

Synthesis of Molecular Phenylcalcium Derivatives: Application to the Formation of Biaryls

by Michael Stephen Hill, Kyle G Pearce, Chiara Dinoi, Mary F Mahon, Laurent Maron, Ryan S Schwamm, Andrew S S Wilson
Synthesis of Molecular Phenylcalcium Derivatives: Application to the Formation of Biaryls

Isolable and hydrocarbon-soluble β-diketiminato calcium phenyls are accessible from the reaction of Ph2Hg and [(BDI)CaH]2. The compounds were shown to react with bromoarenes through a direct SNAr displacement of halide, leading to the uncatalyzed formation of biaryl molecules.


Abstract

Hydrocarbon-soluble β-diketiminato phenylcalcium derivatives, which display various modes of Ca−μ2-Ph−Ca bridging, are accessible from reactions of Ph2Hg and [(BDI)CaH]2. Although the resultant compounds are inert toward the C−H bonds of benzene, they yield selective and uncatalyzed biaryl formation when reacted with readily available aryl bromides.

16 Feb 08:51

On the reactivity of Al-group 11 (Cu, Ag, Au) bonds

Dalton Trans., 2022, 51,3913-3924
DOI: 10.1039/D2DT00404F, Paper
Han-Ying Liu, Samuel E. Neale, Michael S. Hill, Mary F. Mahon, Claire L. McMullin
Reactions of the seven-membered cyclic potassium diamidoalumanyl, [K{Al(SiNDipp)}]2 (SiNDipp = {CH2SiMe2NDipp}2; Dipp = 2,6-di-isopropylphenyl), with a variety of Cu(I), Ag(I) and Au(I) chloride N-heterocyclic carbene (NHC) adducts are described.
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03 Feb 10:16

Access to a Labile Monomeric Magnesium Radical by Ball‐Milling

by Dawid Jędrzkiewicz, Jonathan Mai, Jens Langer, Zachary Mathe, Neha Patel, Serena DeBeer, Sjoerd Harder
Access to a Labile Monomeric Magnesium Radical by Ball-Milling

Ball-milling of a magnesium iodide precursor with K/KI gave a mononuclear Mg radical which is stabilized by a CAAC ligand. Although stable in the crystalline state, the complex decomposed rapidly in solution. According to calculations and EPR spectroscopy, most of the spin density is localized on the CAAC ligand.


Abstract

In order to isolate a monometallic Mg radical, the precursor (Am)MgI⋅(CAAC) (1) was prepared (Am=tBuC(N-DIPP)2, DIPP=2,6-diisopropylphenyl, CAAC=cyclic (alkyl)(amino)carbene). Reduction of a solution of 1 in toluene with the reducing agent K/KI led to formation of a deep purple complex that rapidly decomposed. Ball-milling of 1 with K/KI gave the low-valent MgI complex (Am)Mg⋅(CAAC) (2) which after rapid extraction with pentane and crystallization was isolated in 15 % yield. Although a benzene solution of 2 decomposes rapidly to give Mg(Am)2 (3) and unidentified products, the radical is stable in the solid state. Its crystal structure shows planar trigonal coordination at Mg. The extremely short Mg−C distance of 2.056(2) Å indicates strong Mg−CAAC bonding. Calculations and EPR measurements show that most of the spin density is in a π* orbital located at the C−N bond in CAAC, leading to significant C−N bond elongation. This is supported by calculated NPA charges in 2: Mg +1.73, CAAC −0.82. Similar metal-to-CAAC charge transfer was calculated for M0(CAAC)2 and [MI(CAAC)2 +] (M=Be, Mg, Ca) complexes in which the metal charges range from +1.50 to +1.70. Although the spin density of the radical is mainly located at the CAAC ligand, complex 2 reacts as a low-valent MgI complex: reaction with a I2 solution in toluene gave (Am)MgI⋅(CAAC) (1) as the major product.

20 Jan 15:49

[ASAP] Facile Synthesis of the Dicyanophosphide Anion via Electrochemical Activation of White Phosphorus: An Avenue to Organophosphorus Compounds

by Yanbo Mei, Zeen Yan, and Liu Leo Liu

TOC Graphic

Journal of the American Chemical Society
DOI: 10.1021/jacs.1c11087
22 Dec 13:51

The structures of ring-expanded NHC supported copper(I) triphenylstannyls and their phenyl transfer reactivity towards heterocumulenes

Dalton Trans., 2022, 51,831-835
DOI: 10.1039/D1DT03109K, Communication
Open Access Open Access
Rex S. C. Charman, Mary F. Mahon, John P. Lowe, David J. Liptrot
A copper(I) stannyl supported by a ring-expanded N-heterocyclic carbene has been synthesised and its reactivity towards heterocumulenes has been investigated.
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29 Nov 13:02

Isocyanate deoxygenation by a molecular magnesium silanide

Dalton Trans., 2021, Advance Article
DOI: 10.1039/D1DT03775G, Paper
Open Access Open Access
Creative Commons Licence&nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Bibian Okokhere-Edeghoghon, Samuel E. Neale, Michael S. Hill, Mary F. Mahon, Claire L. McMullin
A molecular magnesium silanide is shown through a combined synthetic and computational study to effect siloxide formation and isocyanate deoxgenation via the initial formation of magnesium silamidate intermediates.
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23 Nov 20:22

A short, versatile route towards benzothiadiazinyl radicals

Chem. Sci., 2021, Advance Article
DOI: 10.1039/D1SC04248C, Edge Article
Open Access Open Access
Andryj M. Borys, Ewan R. Clark, Paul J. Saines, Antonio Alberola, Jeremy M. Rawson
A family of 1,2,4-benzothiadiazinyl radicals are accessible from 1,2,4-benzothiadiazine 1-chlorides which can be prepared in a single step by treatment of N-arylamidines in neat thionyl chloride at reflux.
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18 Oct 09:50

[ASAP] Reductive Dimerization of CO by a Na/Mg(I) Diamide

by Han-Ying Liu, Ryan J. Schwamm, Samuel E. Neale, Michael S. Hill, Claire L. McMullin, and Mary F. Mahon

TOC Graphic

Journal of the American Chemical Society
DOI: 10.1021/jacs.1c09467
30 Sep 10:03

A Benzodiphosphaborolediide

by Kyle G. Pearce, Elinor P. F. Canham, John F. Nixon, Ian R. Crossley
A Benzodiphosphaborolediide

The 1,3-diphosphaborolediide ligand motif, a hitherto missing member of the “hetero-Cp“ family, is obtained within an indenyl scaffold as its dilithium salt, as both thf and TMEDA solvates. This dianionic ligand exhibits aromaticity commensurate with its hybrid phospholide-borolediide nature, as is determined by NICS calculations and observed experimentally for both lithium salts. Additionally, coordination to zero-valent molybdenum is achieved, demonstrating a capacity to to coordinate readily as a π- and bridging π-,σ-type ligand.


Abstract

The first example of a diphosphaborolediide, the benzo-fused [C6H4P2BPh]2− (12− ), is prepared from ortho-bis(phosphino)benzene (C6H4{PH2}) and dichlorophenylborane, via a sequential lithiation approach. The dilithio-salt can be obtained as an oligomeric THF solvate or discrete TMEDA adduct, both of which are fully characterized, including by X-ray diffraction. Alongside NICS calculations, data strongly suggest some aromaticity within 12− , which is further supported by preliminary coordination studies that demonstrate η5-coordination to a zerovalent molybdenum center, as observed crystallographically for the oligomeric [{Mo(CO)35-1)}{μ-η1-Mo(CO)3(TMEDA)}2] ⋅ [μ-Li(THF)][μ-Li(TMEDA)].