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Liu L, Lo SK, Smith C, Goicoechea JM. Pincer-Supported Gallium Complexes for the Catalytic Hydroboration of Aldehydes, Ketones and Carbon Dioxide. Chemistry 2021; 27:17379-17385. [PMID: 34623001 PMCID: PMC9297891 DOI: 10.1002/chem.202103009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Indexed: 12/16/2022]
Abstract
Gallium hydrides stabilised by primary and secondary amines are scarce due to their propensity to eliminate dihydrogen. Consequently, their reactivity has received limited attention. The synthesis of two novel gallium hydride complexes HGa(THF)[ON(H)O] and H2Ga[μ2‐ON(H)O]Ga[ON(H)O] ([ON(H)O]2−=N,N‐bis(3,5‐di‐tert‐butyl‐2‐phenoxy)amine) is described and their reactivity towards aldehydes and ketones is explored. These reactions afford alkoxide‐bridged dimers through 1,2‐hydrogallation reactions. The gallium hydrides can be regenerated through Ga−O/B−H metathesis from the reaction of such dimers with pinacol borane (HBpin) or 9‐borabicyclo[3.3.1]nonane (9‐BBN). These observations allowed us to target the catalytic reduction of carbonyl substrates (aldehydes, ketones and carbon dioxide) with low catalyst loadings at room temperature.
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Roy MMD, Hicks J, Vasko P, Heilmann A, Baston A, Goicoechea JM, Aldridge S. Probing the Extremes of Covalency in M−Al bonds: Lithium and Zinc Aluminyl Compounds. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202109416] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Feld J, Wilson DWN, Goicoechea JM. Contrasting E-H Bond Activation Pathways of a Phosphanyl-Phosphagallene. Angew Chem Int Ed Engl 2021; 60:22057-22061. [PMID: 34383991 PMCID: PMC8518045 DOI: 10.1002/anie.202109334] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Indexed: 11/16/2022]
Abstract
The reactivity of the phosphanyl‐phosphagallene, [H2C{N(Dipp)}]2PP=Ga(Nacnac) (Nacnac=HC[C(Me)N(Dipp)]2; Dipp=2,6‐iPr2C6H3) towards a series of reagents possessing E−H bonds (primary amines, ammonia, water, phenylacetylene, phenylphosphine, and phenylsilane) is reported. Two contrasting reaction pathways are observed, determined by the polarity of the E−H bonds of the substrates. In the case of protic reagents (δ−E−Hδ+), a frustrated Lewis pair type of mechanism is operational at room temperature, in which the gallium metal centre acts as a Lewis acid and the pendant phosphanyl moiety deprotonates the substrates. Interestingly, at elevated temperatures both NH2iPr and ammonia can react via a second, higher energy, pathway resulting in the hydroamination of the Ga=P bond. By contrast, with hydridic reagents (δ+E−Hδ−), such as phenylsilane, hydroelementation of the Ga=P bond is exclusively observed, in line with the polarisation of the Si−H and Ga=P bonds.
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Feld J, Wilson DWN, Goicoechea JM. Contrasting E−H Bond Activation Pathways of a Phosphanyl‐Phosphagallene. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202109334] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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30
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Roy MMD, Hicks J, Vasko P, Heilmann A, Baston AM, Goicoechea JM, Aldridge S. Probing the Extremes of Covalency in M-Al bonds: Lithium and Zinc Aluminyl Compounds. Angew Chem Int Ed Engl 2021; 60:22301-22306. [PMID: 34396660 DOI: 10.1002/anie.202109416] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/10/2021] [Indexed: 11/08/2022]
Abstract
Synthetic routes to lithium, magnesium, and zinc aluminyl complexes are reported, allowing for the first structural characterization of an unsupported lithium-aluminium bond. Crystallographic and quantum-chemical studies are consistent with the presence of a highly polar Li-Al interaction, characterized by a low bond order and relatively little charge transfer from Al to Li. Comparison with magnesium and zinc aluminyl systems reveals changes to both the M-Al bond and the (NON)Al fragment (where NON=4,5-bis(2,6-diisopropylanilido)-2,7-di-tert-butyl-9,9-dimethylxanthene), consistent with a more covalent character, with the latter complex being shown to react with CO2 via a pathway that implies that the zinc centre acts as the nucleophilic partner.
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Abbenseth J, Goicoechea JM. A phosphorus analog of a bimetallic dinitrogen complex. Chem 2021. [DOI: 10.1016/j.chempr.2021.06.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Abstract
![]()
The cyanide ion plays
a key role in a number of industrially relevant
chemical processes, such as the extraction of gold and silver from
low grade ores. Metal cyanide compounds were arguably some of the
earliest coordination complexes studied and can be traced back to
the serendipitous discovery of Prussian blue by Diesbach in 1706.
By contrast, heavier cyanide analogues, such as the cyaphide ion,
C≡P–, are virtually unexplored despite the
enormous potential of such ions as ligands in coordination compounds
and extended solids. This is ultimately due to the lack of a suitable
synthesis of cyaphide salts. Herein we report the synthesis and isolation
of several magnesium–cyaphido complexes by reduction of iPr3SiOCP with a magnesium(I) reagent.
By analogy with Grignard reagents, these compounds can be used for
the incorporation of the cyaphide ion into the coordination sphere
of metals using a simple salt-metathesis protocol.
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Faria EN, Jupp AR, Goicoechea JM. Novel primary phosphinecarboxamides derived from diamines. Dalton Trans 2021; 50:6991-6996. [PMID: 33949541 DOI: 10.1039/d1dt01198g] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We describe the synthesis of N-functionalised phosphinecarboxamides obtained by reaction of the 2-phosphaethynolate anion (PCO-) with diamines, specifically hydrazine, methylenediamine and ethylenediamine, in the presence of acid. The resulting neutral compounds can be deprotonated to generate phosphide anions that, when further reacted with electrophiles, form secondary phosphines.
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Watt FA, Burkhardt L, Schoch R, Mitzinger S, Bauer M, Weigend F, Goicoechea JM, Tambornino F, Hohloch S. η
3
‐Coordination and Functionalization of the 2‐Phosphaethynthiolate Anion at Lanthanum(III)**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202100559] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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35
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Watt FA, Burkhardt L, Schoch R, Mitzinger S, Bauer M, Weigend F, Goicoechea JM, Tambornino F, Hohloch S. η 3 -Coordination and Functionalization of the 2-Phosphaethynthiolate Anion at Lanthanum(III)*. Angew Chem Int Ed Engl 2021; 60:9534-9539. [PMID: 33565689 PMCID: PMC8252525 DOI: 10.1002/anie.202100559] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Indexed: 01/08/2023]
Abstract
We present the η3 -coordination of the 2-phosphaethynthiolate anion in the complex (PN)2 La(SCP) (2) [PN=N-(2-(diisopropylphosphanyl)-4-methylphenyl)-2,4,6-trimethylanilide)]. Structural comparison with dinuclear thiocyanate-bridged (PN)2 La(μ-1,3-SCN)2 La(PN)2 (3) and azide-bridged (PN)2 La(μ-1,3-N3 )2 La(PN)2 (4) complexes indicates that the [SCP]- coordination mode is mainly governed by electronic, rather than steric factors. Quantum mechanical investigations reveal large contributions of the antibonding π*-orbital of the [SCP]- ligand to the LUMO of complex 2, rendering it the ideal precursor for the first functionalization of the [SCP]- anion. Complex 2 was therefore reacted with CAACs which induced a selective rearrangement of the [SCP]- ligand to form the first CAAC stabilized group 15-group 16 fulminate-type complexes (PN)2 La{SPC(R CAAC)} (5 a,b, R=Ad, Me). A detailed reaction mechanism for the SCP-to-SPC isomerization is proposed based on DFT calculations.
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Schreiber RE, Goicoechea JM. Phosphine Carboxylate-Probing the Edge of Stability of a Carbon Dioxide Adduct with Dihydrogenphosphide. Angew Chem Int Ed Engl 2021; 60:3759-3767. [PMID: 33135848 DOI: 10.1002/anie.202013914] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Indexed: 11/08/2022]
Abstract
We present a new adduct of carbon dioxide with dihydrogenphosphide, that may be prepared either by direct reaction of NaPH2 with carbon dioxide or by hydrolysis of the phosphaethynolate ion (PCO- ). In this hydrolysis transformation, a new mechanism is proposed for the electrophilic reactivity of the phosphaethynolate ion. Protonation to form phosphine carboxylic acid (PH2 COOH) and functionalization to form esters is shown to increase the strength of the P-C interaction, allowing for comparisons to be drawn between this species and the analogous carbamic (NH2 COOH) and carbonic acids (H2 CO3 ). Functionalization of the oxygen atom is found to stabilize the phosphine carboxylate while also allowing solubility in organic solvents whereas phosphorus functionalization is shown to facilitate decarboxylation. Substituent migration occurs in some cases.
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37
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Schreiber RE, Goicoechea JM. Phosphine Carboxylate—Probing the Edge of Stability of a Carbon Dioxide Adduct with Dihydrogenphosphide. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202013914] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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38
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Caise A, Hicks J, Ángeles Fuentes M, Goicoechea JM, Aldridge S. Partnering a Three-Coordinate Gallium Cation with a Hydroborate Counter-Ion for the Catalytic Hydrosilylation of CO 2. Chemistry 2021; 27:2138-2148. [PMID: 33169886 DOI: 10.1002/chem.202004408] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/08/2020] [Indexed: 12/16/2022]
Abstract
A novel β-diketiminate stabilized gallium hydride, (Dipp L)Ga(Ad)H (where (Dipp L)={HC(MeCDippN)2 }, Dipp=2,6-diisopropylphenyl and Ad=1-adamantyl), has been synthesized and shown to undergo insertion of carbon dioxide into the Ga-H bond under mild conditions. In this case, treatment of the resulting κ1 -formate complex with triethylsilane does not lead to regeneration of the hydride precursor. However, when combined with B(C6 F5 )3 , (Dipp L)Ga(Ad)H catalyses the reductive hydrosilylation of CO2 . Under stoichiometric conditions, the addition of one equivalent of B(C6 F5 )3 to (Dipp L)Ga(Ad)H leads to the formation of a 3-coordinate cationic gallane complex, partnered with a hydroborate anion, [(Dipp L)Ga(Ad)][HB(C6 F5 )3 ]. This complex rapidly hydrometallates carbon dioxide and catalyses the selective reduction of CO2 to the formaldehyde oxidation level at 60 °C in the presence of Et3 SiH (yielding H2 C(OSiEt3 )2 ). When catalysis is undertaken in the presence of excess B(C6 F5 )3 , appreciable enhancement of activity is observed, with a corresponding reduction in selectivity: the product distribution includes H2 C(OSiEt3 )2 , CH4 and O(SiEt3 )2 . While this system represents proof-of-concept in CO2 hydrosilylation by a gallium hydride system, the TOF values obtained are relatively modest (max. 10 h-1 ). This is attributed to the strength of binding of the formatoborate anion to the gallium centre in the catalytic intermediate (Dipp L)Ga(Ad){OC(H)OB(C6 F5 )3 }, and the correspondingly slow rate of the turnover-limiting hydrosilylation step. In turn, this strength of binding can be related to the relatively high Lewis acidity measured for the [(Dipp L)Ga(Ad)]+ cation (AN=69.8).
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39
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Townrow OPE, Weller AS, Goicoechea JM. Cluster expansion and vertex substitution pathways in nickel germanide Zintl clusters. Chem Commun (Camb) 2021; 57:7132-7135. [PMID: 34180473 DOI: 10.1039/d1cc02912f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
We describe the reactivity of the hypersilyl-functionalized Zintl cluster salt K[Ge9(Hyp)3] towards the nickel reagents Ni(COD)2 and Ni(Cp)2, which gives rise to markedly different complexes. In the case of Ni(COD)2 (COD = 1,5-cyclooctadiene), a dianionic sandwich-like cluster [Ni{Ge9(Hyp)3}2]2- (1) was obtained, in line with a simple ligand substitution reaction of COD by [Ge9(Hyp)3]-. By contrast, when an analogous reaction with Ni(Cp)2 (Cp = cyclopentadienyl) was performed, vertex substitution of the [Ge9(Hyp)3]- precursor was observed, giving rise to the nine-vertex nido-cluster (Cp)Ni[Ge8(Hyp)3] (2). This is the first instance of vertex substitution at a hypersilyl-functionalized Zintl cluster cage. The electrochemical behavior of these compounds was explored and showed reversible redox behaviour for both clusters.
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40
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Wilson DWN, Feld J, Goicoechea JM. A Phosphanyl-Phosphagallene that Functions as a Frustrated Lewis Pair. Angew Chem Int Ed Engl 2020; 59:20914-20918. [PMID: 32615007 PMCID: PMC7693089 DOI: 10.1002/anie.202008207] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Indexed: 12/05/2022]
Abstract
Phosphagallenes (1 a/1 b) featuring double bonds between phosphorus and gallium were synthesized by reaction of (phosphanyl)phosphaketenes with the gallium carbenoid Ga(Nacnac) (Nacnac=HC[C(Me)N(2,6-i-Pr2 C6 H3 )]2 ). The stability of these species is dependent on the saturation of the phosphanyl moiety. 1 a, which bears an unsaturated phosphanyl ring, rearranges in solution to yield a spirocyclic compound (2) which contains a P=P bond. The saturated variant 1 b is stable even at elevated temperatures. 1 b behaves as a frustrated Lewis pair capable of activation of H2 and forms a 1:1 adduct with CO2 .
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41
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Wilson DWN, Feld J, Goicoechea JM. A Phosphanyl‐Phosphagallene that Functions as a Frustrated Lewis Pair. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008207] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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42
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Wilson DWN, Myers WK, Goicoechea JM. Synthesis and decarbonylation chemistry of gallium phosphaketenes. Dalton Trans 2020; 49:15249-15255. [PMID: 33084675 DOI: 10.1039/d0dt03174g] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of gallium phosphaketenyl complexes supported by a 1,2-bis(aryl-imino)acenaphthene ligand (Dipp-Bian) are reported. Photolysis of one such species induced decarbonylation to afford a gallium substituted diphosphene. Addition of Lewis bases, specifically trimethylphosphine and the gallium carbenoid Ga(Nacnac) (Nacnac = HC[C(Me)N-(C6H3)-2,6-iPr2]2), resulted in displacement of the phosphaketene carbonyl to yield base-stabilised phosphinidenes. In several of these transformations, the redox non-innocence of the Dipp-Bian ligand was found to give rise to radical intermediates and/or side-products.
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43
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Hicks J, Vasko P, Heilmann A, Goicoechea JM, Aldridge S. Arene C-H Activation at Aluminium(I): meta Selectivity Driven by the Electronics of S N Ar Chemistry. Angew Chem Int Ed Engl 2020; 59:20376-20380. [PMID: 32722863 PMCID: PMC7693242 DOI: 10.1002/anie.202008557] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Indexed: 12/14/2022]
Abstract
The reactivity of the electron-rich anionic AlI aluminyl compound K2 [(NON)Al]2 (NON=4,5-bis(2,6-diisopropylanilido)-2,7-di-tert-butyl-9,9-dimethylxanthene) towards mono- and disubstituted arenes is reported. C-H activation chemistry with n-butylbenzene gives exclusively the product of activation at the arene meta position. Mechanistically, this transformation proceeds in a single step via a concerted Meisenheimer-type transition state. Selectivity is therefore based on similar electronic factors to classical SN Ar chemistry, which implies the destabilisation of transition states featuring electron-donating groups in either ortho or para positions. In the cases of toluene and the three isomers of xylene, benzylic C-H activation is also possible, with the product(s) formed reflecting the feasibility (or otherwise) of competing arene C-H activation at a site which is neither ortho nor para to a methyl substituent.
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44
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Townrow OE, Chung C, Macgregor SA, Weller AS, Goicoechea JM. A Neutral Heteroatomic Zintl Cluster for the Catalytic Hydrogenation of Cyclic Alkenes. J Am Chem Soc 2020; 142:18330-18335. [PMID: 33052653 PMCID: PMC7596751 DOI: 10.1021/jacs.0c09742] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Indexed: 12/31/2022]
Abstract
We report on the synthesis of an alkane-soluble Zintl cluster, [η4-Ge9(Hyp)3]Rh(COD), that can catalytically hydrogenate cyclic alkenes such as 1,5-cyclooctadiene and cis-cyclooctene. This is the first example of a well-defined Zintl-cluster-based homogeneous catalyst.
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45
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Wilson DWN, Mehta M, Franco MP, McGrady JE, Goicoechea JM. Linkage Isomerism Leading to Contrasting Carboboration Chemistry: Access to Three Constitutional Isomers of a Borylated Phosphaalkene. Chemistry 2020; 26:13462-13467. [PMID: 32495945 PMCID: PMC7702093 DOI: 10.1002/chem.202002226] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Indexed: 12/03/2022]
Abstract
We describe the reactivity of two linkage isomers of a boryl-phosphaethynolate, [B]OCP and [B]PCO (where [B]=N,N'-bis(2,6-diisopropylphenyl)-2,3-dihydro-1H-1,3,2-diazaboryl), towards tris- (pentafluorophenyl)borane (BCF). These reactions afforded three constitutional isomers all of which contain a phosphaalkene core. [B]OCP reacts with BCF through a 1,2 carboboration reaction to afford a novel phosphaalkene, E-[B]O{(C6 F5 )2 B}C=P(C6 F5 ), which subsequently undergoes a rearrangement process involving migration of both the boryloxy and pentafluorophenyl substituents to afford Z-{(C6 F5 )2 B}(C6 F5 )C=PO[B]. By contrast, [B]PCO undergoes a 1,3-carboboration process accompanied by migration of the N,N'-bis(2,6-diisopropylphenyl)-2,3-dihydro-1H-1,3,2-diazaboryl to the carbon centre.
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Zovko C, Bestgen S, Schoo C, Görner A, Goicoechea JM, Roesky PW. Cover Feature: A Phosphine Functionalized β‐Diketimine Ligand for the Synthesis of Manifold Metal Complexes (Chem. Eur. J. 58/2020). Chemistry 2020. [DOI: 10.1002/chem.202002131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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47
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Zovko C, Bestgen S, Schoo C, Görner A, Goicoechea JM, Roesky PW. A Phosphine Functionalized β-Diketimine Ligand for the Synthesis of Manifold Metal Complexes. Chemistry 2020; 26:13191-13202. [PMID: 32285968 PMCID: PMC7693294 DOI: 10.1002/chem.202001357] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Indexed: 01/23/2023]
Abstract
A bis(diphenyl)-phosphine functionalized β-diketimine (PNac-H) was synthesized as a flexible ligand for transition metal complexes. The newly designed ligand features symmetrically placed phosphine moieties around a β-diketimine unit, forming a PNNP-type pocket. Due to the hard and soft donor atoms (N vs. P) the ligand can stabilize various coordination polyhedra. A complete series ranging from coordination numbers 2 to 6 was realized. Linear, trigonal planar, square planar, tetrahedral, square pyramidal, and octahedral coordination arrangements containing the PNac-ligand around the metal center were observed by using suitable metal sources. Hereby, PNac-H or its anion PNac- acts as mono-, bi- and tetradendate ligand. Such a broad flexibility is unusual for a rigid tetradentate system. The structural motifs were realized by treatment of PNac-H with a series of late transition metal precursors, for example, silver, gold, nickel, copper, platinum, and rhodium. The new complexes have been fully characterized by single crystal X-ray diffraction, NMR, IR, UV/Vis spectroscopy, mass spectrometry as well as elemental analysis. Additionally, selected complexes were investigated regarding their photophysical properties. Thus, PNac-H proved to be an ideal ligand platform for the selective coordination and stabilization of various metal ions in diverse polyhedra and oxidation states.
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48
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Hicks J, Vasko P, Heilmann A, Goicoechea JM, Aldridge S. Arene C−H Activation at Aluminium(I):
meta
Selectivity Driven by the Electronics of S
N
Ar Chemistry. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008557] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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49
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Hicks J, Vasko P, Goicoechea JM, Aldridge S. The Aluminyl Anion: A New Generation of Aluminium Nucleophile. Angew Chem Int Ed Engl 2020; 60:1702-1713. [DOI: 10.1002/anie.202007530] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Indexed: 02/03/2023]
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50
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Abbenseth J, Goicoechea JM. Recent developments in the chemistry of non-trigonal pnictogen pincer compounds: from bonding to catalysis. Chem Sci 2020; 11:9728-9740. [PMID: 34094237 PMCID: PMC8162179 DOI: 10.1039/d0sc03819a] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 08/18/2020] [Indexed: 01/01/2023] Open
Abstract
The combination of well-established meridionally coordinating, tridentate pincer ligands with group 15 elements affords geometrically constrained non-trigonal pnictogen pincer compounds. These species show remarkable activity in challenging element-hydrogen bond scission reactions, such as the activation of ammonia. The electronic structures of these compounds and the implications they have on their electrochemical properties and transition metal coordination are described. Furthermore, stoichiometric and catalytic bond forming reactions involving B-H, N-H and O-H bonds as well as carbon nucleophiles are presented.
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