Co-reporter:Mark A. Bradley;Chris Birchall;Alexander J. Blake;William Lewis;Graeme J. Moxey
Dalton Transactions 2017 vol. 46(Issue 12) pp:4101-4110
Publication Date(Web):2017/03/21
DOI:10.1039/C7DT00471K
The reactions between magnesium or zinc alkyls and 1,8-bis(triorganosilyl)diaminonaphthalenes afford the 1,8-bis(triorganosilyl)diamidonaphthalene complexes with elimination of alkanes. The reaction between 1,8-C10H6(NSiMePh2H)2 and one or two equivalents of MgnBu2 affords two complexes with differing coordination environments for the magnesium; the reaction between 1,8-C10H6(NSiMePh2H)2 and MgnBu2 in a 1 : 1 ratio affords 1,8-C10H6(NSiMePh2)2{Mg(THF)2} (1), which features a single magnesium centre bridging both ligand nitrogen donors, whilst treatment of 1,8-C10H6(NSiR3H)2 (R3 = MePh2, iPr3) with two equivalents of MgnBu2 affords the bimetallic complexes 1,8-C10H6(NSiR3)2{nBuMg(THF)}2 (R3 = MePh22, R3 = iPr33), which feature four-membered Mg2N2 rings. Similarly, 1,8-C10H6(NSiiPr3)2{MeMg(THF)}2 (4) and 1,8-C10H6(NSiMePh2)2{ZnMe}2 (5) are formed through reactions with the proligands and two equivalents of MMe2 (M = Mg, Zn). The reaction between 1,8-C10H6(NSiMePh2H)2 and two equivalents of MeMgX affords the bimetallic complexes 1,8-C10H6(NSiMePh2)2(XMgOEt2)2 (X = Br 6; X = I 7). Very small amounts of [1,8-C10H6(NSiMePh2)2{IMg(OEt2)}]2 (8), formed through the coupling of two diamidonaphthalene ligands at the 4-position with concomitant dearomatisation of one of the naphthyl arene rings, were also isolated from a solution of 7.
Co-reporter:Helen R. Sharpe;Ana M. Geer;Huw E. L. Williams;Toby J. Blundell;William Lewis;Alexander J. Blake
Chemical Communications 2017 vol. 53(Issue 5) pp:937-940
Publication Date(Web):2017/01/10
DOI:10.1039/C6CC07243G
Two- and three-coordinate m-terphenyl complexes of manganese and iron are efficient catalysts for the selective cyclotrimerisation of primary aliphatic isocyanates affording isocyanurates in short reaction times and under mild conditions.
Co-reporter:Christopher Birchall, Graeme J. Moxey, Jonathan McMaster, Alexander J. Blake, William Lewis, Deborah L. Kays
Inorganica Chimica Acta 2017 Volume 458(Volume 458) pp:
Publication Date(Web):24 March 2017
DOI:10.1016/j.ica.2016.12.029
•An unsupported bond between an alkaline earth element and a transition metal.•M-M bond best described by a donor/acceptor model with large ionic contribution.•Calculations and spectroscopy identify a predominantly ionic Mg–Fe bond.The phosphinimine, trimethylsilyl-substituted BIPM ligand [BIPM = bis(iminophosphorano)methanide] has been used to stabilise CH(Ph2PNSiMe3)2MgFe(η5-C5H5)(CO)2 (1), which is a structurally authenticated complex exhibiting a direct, unsupported bond between an alkaline earth metal and a transition metal. The FTIR-measured carbonyl stretching frequencies for this complex suggest that there is a polarisation of charge from the transition metal fragment to the magnesium centre. The presence of a polar metal-metal bond in 1 is confirmed by DFT calculations, which suggest that the Mg–Fe bond is predominantly ionic in nature.CH(Ph2PNSiMe3)2Mg−Fe(η5-C5H5)(CO)2 features an unsupported alkaline earth-transition metal bond. Experimental methods and DFT calculations identify that the Mg–Fe bond is predominantly ionic in nature.Download high-res image (47KB)Download full-size image
Co-reporter:Graeme J. Moxey;Alexer J. Blake;William Lewis
European Journal of Inorganic Chemistry 2015 Volume 2015( Issue 36) pp:5892-5902
Publication Date(Web):
DOI:10.1002/ejic.201501239
Abstract
The synthesis of the guanidine MesN{C(NCy2)}N(H)Mes (LH; Mes = 2,4,6-Me3C6H2, Cy = cyclohexyl), and its use as a proligand for the synthesis of alkaline earth metal complexes are reported. Described herein are (i) an unusual Hauser base cubane, (ii) a homoleptic and a base-stabilized magnesium complex featuring the same guanidinate ligands, and (iii) the comparison of a series of alkaline earth (Mg, Ca, Sr, Ba) bis(guanidinate) complexes, which allows the opportunity to compare the changing trends in bonding as the Group is descended. The reaction between LH and MeMgI(OEt2)2 yields the Hauser base as a mixture of the tetramer [Mg4L4(μ3-I)4] (1a) and dimer [Mg2L2(μ-I)2(OEt2)2] (1b), and the reaction with two equivalents of MgnBu2 leads to the formation of four-coordinate [MgL2] (2), which features a square-planar geometry for the magnesium cation, or five-coordinate [MgL2(THF)] (3), depending on the solvent used. 1a is the first crystallographically-characterized cubane structure to consist of four LAeX (L = ligand, X = halide) units. The complexes [AeL2(THF)2] (Ae = Ca, 4; Ae = Sr, 5) and [BaL2] (6) were synthesized via redox transmetallation/ligand exchange reactions. Complex 6 is the first example of a homoleptic, monomeric barium complex of the NCN ligand family, with the structure stabilized by a number of barium-arene interactions in the solid state.
Co-reporter:Dr. Fabrizio Ortu;Dr. Graeme J. Moxey; Alexer J. Blake;Dr. William Lewis;Dr. Deborah L. Kays
Chemistry - A European Journal 2015 Volume 21( Issue 18) pp:6949-6956
Publication Date(Web):
DOI:10.1002/chem.201406490
Abstract
1,3,6,8-Tetra-tert-butylcarbazol-9-yl and 1,8-diaryl-3,6-di(tert-butyl)carbazol-9-yl ligands have been utilized in the synthesis of potassium and magnesium complexes. The potassium complexes (1,3,6,8-tBu4carb)K(THF)4 (1; carb=C12H4N), [(1,8-Xyl2-3,6-tBu2carb)K(THF)]2 (2; Xyl=3,5-Me2C6H3) and (1,8-Mes2-3,6-tBu2carb)K(THF)2 (3; Mes=2,4,6-Me3C6H2) were reacted with MgI2 to give the Hauser bases 1,3,6,8-tBu4carbMgI(THF)2 (4) and 1,8-Ar2-3,6-tBu2carbMgI(THF) (Ar=Xyl 5, Ar=Mes 6). Structural investigations of the potassium and magnesium derivatives highlight significant differences in the coordination motifs, which depend on the nature of the 1- and 8-substituents: 1,8-di(tert-butyl)-substituted ligands gave π-type compounds (1 and 4), in which the carbazolyl ligand acts as a multi-hapto donor, with the metal cations positioned below the coordination plane in a half-sandwich conformation, whereas the use of 1,8-diaryl substituted ligands gave σ-type complexes (2 and 6). Space-filling diagrams and percent buried volume calculations indicated that aryl-substituted carbazolyl ligands offer a steric cleft better suited to stabilization of low-coordinate magnesium complexes.
Co-reporter:Graeme J. Moxey, Fabrizio Ortu, Leon Goldney Sidley, Helen N. Strandberg, Alexander J. Blake, William Lewis and Deborah L. Kays
Dalton Transactions 2014 vol. 43(Issue 12) pp:4838-4846
Publication Date(Web):24 Jan 2014
DOI:10.1039/C3DT53234H
Condensation reactions of carboxylic acids and anilines in the presence of polyphosphoric acid trimethylsilyl ester (PPSE) afforded a range of sterically demanding N,N′-bis(aryl)amidines, RN{C(R′)}N(H)R [R = Mes (Mes = 2,4,6-trimethylphenyl), R′ = Cy (Cy = cyclohexyl) L1H; R = Dipp (Dipp = 2,6-diisopropylphenyl), R′ = Cy L2H; R = Mes, R′ = Ph L3H; R = Dipp, R′ = Ph L4H; R = Mes, R′ = Dmp (Dmp = 3,5-dimethylphenyl) L5H; R = Dipp, R′ = Dmp L6H; R = Dmp, R′ = Cy L7H]. Amidines L1H–L7H have been characterised spectroscopically, and for L5H and L6H, by X-ray crystallography. Treatment of the amidines with di-n-butylmagnesium in THF solution afforded the monomeric magnesium bis(amidinates) [Mg(L1)2(THF)] 1, [Mg(L2)2] 2, [Mg(L3)2(THF)] 3, [Mg(L5)2(THF)] 5, [Mg(L6)2] 6, [Mg(L7)2] 7, and the magnesium mono(amidinate) complex [Mg(L4)(nBu)] 4. These complexes have been characterised spectroscopically, with 1–3, 5 and 6 also being structurally authenticated. Comparison of the magnesium bis(amidinate) complexes reveals that the steric bulk of the amidinate ligand influences both the solid state structure and solution behaviour of these complexes.
Co-reporter:Toby J. Blundell, Fiona R. Hastings, Benjamin M. Gridley, Graeme J. Moxey, William Lewis, Alexander J. Blake and Deborah L. Kays
Dalton Transactions 2014 vol. 43(Issue 38) pp:14257-14264
Publication Date(Web):08 Apr 2014
DOI:10.1039/C4DT00647J
Three m-terphenyl ligands 2,6-Ar2C6H3− [Ar = 2,6-Me2C6H3 (2,6-Xyl); 3,5-Me2C6H3 (3,5-Xyl); 2,3,4,5,6-Me5C6 (Pmp)] have been used to stabilise three series of two-coordinate Group 12 diaryl complexes; (2,6-Ar2C6H3)2M [M = Zn, Cd, Hg, Ar = 2,6-Xyl 1–3, 3,5-Xyl 4–6, Pmp 7–9], where differing steric demands on the metal centres are imparted. These are the first homoleptic d-block complexes featuring any of these ligands. Complexes 1–9 have been characterised in solution and the solid state; the analysis of structural changes produced by differences in ligand properties is reported. In particular, complexes 4–6 show smaller C–M–C bond angles and contain secondary ligand interactions that are not seen in the analogous complexes 1–3 and 7–9.
Co-reporter:Benjamin M. Gridley, Toby J. Blundell, Graeme J. Moxey, William Lewis, Alexander J. Blake and Deborah L. Kays
Chemical Communications 2013 vol. 49(Issue 84) pp:9752-9754
Publication Date(Web):10 Sep 2013
DOI:10.1039/C3CC46384B
The reaction between sterically demanding m-terphenyl lithiate complexes and cadmium dihalides yields unusual cubanes where changes in ligand bulk afford different formulations, in particular a rare heterodicubane structure.
Co-reporter:Fabrizio Ortu ; Graeme J. Moxey ; Alexander J. Blake ; William Lewis
Inorganic Chemistry 2013 Volume 52(Issue 21) pp:12429-12439
Publication Date(Web):October 17, 2013
DOI:10.1021/ic4012923
The synthesis and characterization of magnesium and calcium complexes of sterically demanding aminopyridinato ligands is reported. The reaction of the 2-Me3SiNH-6-MeC5H3N (L1H), 2-MePh2SiNH-6-MeC5H3N (L2H), and 2-Me3SiNH-6-PhC5H3N (L3H) with KH in tetrahydrofuran (THF) yielded potassium salts L1K(thf)0.5 (1), L2K (2), and L3K(thf)0.5 (3), which, through subsequent reaction with MgI2 and CaI2, afforded the homoleptic complexes (L)2Ae(thf)n [L = L1, Ae = Mg, n = 1 (4); L = L2, Ae = Mg, n = 0 (5); L = L3, Ae = Mg, n = 0 (6); L = L2, Ae = Ca, n = 2 (7)] and heterobimetallic calciates {[(L)3Ca]K}∞ [L = L1 (8); L = L2 (9)]. The solid state structure of 8 reveals a polymeric arrangement in which the calciate units are interlocked by bridging potassium ions. Metalation reactions between L1H or L2H and (nBu)2Mg lead to the solvent-free compounds (L)2Mg [L = L1 (10); L = L2 (5)]. The bridged butyl mixed-metal complex [(L1)Li(μ2-nBu)Mg(L1)]∞ (11) was also obtained via a cocomplexation reaction with nBuLi and (nBu)2Mg. 11, which adopts a monodimensional polymeric array in the solid state, is a rare example of an alkyl-bridged Li/Mg complex and the first complex to feature an unsupported bridging butyl interaction between two metals. Changing the cocomplexation reaction conditions, the order of reagents added to the reactions mixture, and with the use of a coordinating solvent (tetrahydrofuran) formed the magnesiate complex (L1)3MgLi(thf) (12).
Co-reporter:Rhiannon S. Moorhouse, Graeme J. Moxey, Fabrizio Ortu, Thomas J. Reade, William Lewis, Alexander J. Blake, and Deborah L. Kays
Inorganic Chemistry 2013 Volume 52(Issue 5) pp:2678-2683
Publication Date(Web):February 14, 2013
DOI:10.1021/ic302727w
The solid state structures of alkali metal complexes of the 1,3,6,8-tetra-tert-butylcarbazol-9-yl (tBu4carb–) ligand are compared. Lithium complex [tBu4carbLi]2 ([1]2) is a dimer in the solid state featuring a planar LiNLiN rhomboid ring, with the differing Li–N distances within the ring due to the effects of σ- and π-interactions. Recrystallization of lithium, sodium, and potassium complexes of the 1,3,6,8-tetra-tert-butylcarbazol-9-yl ligand from THF leads to the formation of tBu4carbLi(THF)2 (1·2THF), tBu4carbNa(THF)3 (2·3THF), and tBu4carbK(THF)4 (3·4THF), respectively, in the solid state. For these THF adducts, on proceeding from lithium to sodium to potassium there is an increase in hapticity of the binding of the carbazol-9-yl ligands to the metal cations, mirroring the increasing ionic bonding character in these compounds.
Co-reporter:Benjamin M. Gridley;Dr. Graeme J. Moxey;Dr. William Lewis; Alexer J. Blake ;Dr. Deborah L. Kays
Chemistry - A European Journal 2013 Volume 19( Issue 34) pp:11446-11453
Publication Date(Web):
DOI:10.1002/chem.201301872
Abstract
The synthesis and characterization of the first series of low-coordinate bis(terphenyl) complexes of the Group 12 metals, [Zn(2,6-Naph2C6H3)2] (1), [Cd(OEt2)(2,6-Naph2C6H3)2] (2) and [Hg(OEt2)(2,6-Naph2C6H3)2] (3) (Naph=1-C10H7) are described. The naphthyl substituents of the terphenyl ligands confer considerable steric bulk, and as a result of limited flexibility introduce multiple conformations to these unusual systems. In the solid state, complex 1 features a two-coordinate Zn centre with the ligands oriented in a syn/anti conformation, whereas the three-coordinate distorted T-shaped complexes 2 and 3 feature the ligands in the syn/syn configurations. The results of DFT calculations are in good agreement with the solid-state configurations for these complexes and support the spectroscopic measurements, which indicate several conformers in solution.
Co-reporter:Benjamin M. Gridley, Alexander J. Blake, Adrienne L. Davis, William Lewis, Graeme J. Moxey and Deborah L. Kays
Chemical Communications 2012 vol. 48(Issue 71) pp:8910-8912
Publication Date(Web):20 Jul 2012
DOI:10.1039/C2CC34525K
Cobalt(II) diaryl complexes react with CO to afford Co2(CO)8 and sterically encumbered ketones whose structure varies depending on the nature of the aryl ligands.
Co-reporter:Victoria J. Richards, Alexandra L. Gower, Jasper E. H. B. Smith, E. Stephen Davies, Dorothée Lahaye, Anna G. Slater, William Lewis, Alexander J. Blake, Neil R. Champness and Deborah L. Kays
Chemical Communications 2012 vol. 48(Issue 12) pp:1751-1753
Publication Date(Web):03 Jan 2012
DOI:10.1039/C2CC16047A
The redox processes associated with BODIPY analogues are studied by electrochemical and spectroscopic methods revealing a characteristic profile for the persistent BODIPY radical and quenching of fluorescence upon reduction.
Co-reporter:Alexander J. Blake, William Lewis, Jonathan McMaster, Rhiannon S. Moorhouse, Graeme J. Moxey and Deborah L. Kays
Dalton Transactions 2011 vol. 40(Issue 8) pp:1641-1645
Publication Date(Web):20 Jan 2011
DOI:10.1039/C0DT01710H
The synthesis and characterisation of low-coordinate zinc and cadmium complexes of the sterically demanding 1,3,6,8-tetra-tert-butylcarbazol-9-yl ligand (tBu4carb−) are reported. (tBu4carb)2M (M = Zn 1; M = Cd 2) are the first examples of formally two-coordinate bis-carbazol-9-yl complexes of the Group 12 metals and 2 is the first crystallographically characterised two-coordinate amido complex of cadmium. The structure and bonding within these complexes are explored via a combination of X-ray crystallography and DFT calculations. The solid state structures for these zinc and cadmium complexes differ greatly from each other; not only do the steric demands of the peripheral tert-butyl substituents in these systems act to inhibit solvent coordination, but they also influence the coordination geometry around the metal centres.
Co-reporter:Deborah Kays
Applied Organometallic Chemistry 2011 Volume 25( Issue 6) pp:
Publication Date(Web):
DOI:10.1002/aoc.1748
No abstract is available for this article.
Co-reporter:Alexander J. Blake, Alexandra L. Gower, William Lewis, Graeme J. Moxey, Thomas J. Reade, Deborah L. Kays
Journal of Organometallic Chemistry 2011 696(9) pp: 1787-1791
Publication Date(Web):
DOI:10.1016/j.jorganchem.2010.12.023
Co-reporter:Alexander J. Blake, Nicola L. Gillibrand, Graeme J. Moxey and Deborah L. Kays
Inorganic Chemistry 2009 Volume 48(Issue 22) pp:10837-10844
Publication Date(Web):October 13, 2009
DOI:10.1021/ic901745v
Four low-coordinate transition metal amido complexes featuring sterically demanding 1,8-bis(silylamido)naphthalene ligands are reported. Reaction of one molar equivalent of 1,8-C10H6(NLiSiMe3)2 with ZnCl2 yields the structurally authenticated dimer [1,8-C10H6(NSiMe3)2Zn]2 (1), where the 1,8-bis(silylamido)naphthalene moiety is acting as both a chelating and bridging ligand. The effect on the resulting transition metal complexes of increasing the steric demands of the ligand was investigated, using the triisopropylsilyl-substituted ligand 1,8-C10H6(NSiiPr3)2. Reaction of one molar equivalent of 1,8-C10H6(NLiSiiPr3)2 with ZnCl2 or FeCl2(THF)1.5 yields 1,8-C10H6(NSiiPr3)2M(μ-Cl)Li(THF)3 (M = Zn, 2; M = Fe, 3), respectively; the coordination of the ClLi(THF)3 moiety to the metal center in these compounds is a rare structural motif in the coordination chemistry of the d-block elements. Analogous reaction of 1,8-C10H6(NLiSiiPr3)2 with MnCl2 affords the mixed-metal Li−Mn−amido complex 1,8-C10H6(NSiiPr3)2Li(THF)MnCl(THF) (4) which features an unusual LiMnN2 core.
Co-reporter:Andrew E. Ashley;Andrew R. Cowley;Jennifer C. Green;David R. Johnston;David J. Watkin
European Journal of Inorganic Chemistry 2009 Volume 2009( Issue 17) pp:2547-2552
Publication Date(Web):
DOI:10.1002/ejic.200900170
Abstract
The synthesis and characterisation of the homoleptic transition-metal complexes (1,8-Ph2-3,6-Me2C12H4N)2M (M = Cr, 1; M = Mn, 2; M = Fe, 3; M = Co, 4) are described. Formally two-coordinate, the solid-state structures of 2 and 3 reveal near-linear N–M–N geometries and significant bending of the flanking phenyl groups towards the metal centres. Solid-state magnetic measurements reveal high spin metal centres in 1–4; computational calculations for the model complexes M(1,8-Ph2C12H6N)2 (M = Cr–Co) confirm the presence of high-spin configurations within these bis-carbazolido compounds and an orbital ordering of δ < π < σ for these systems.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Co-reporter:DeborahL. Kays Dr.;Simon Aldridge Dr.
Angewandte Chemie International Edition 2009 Volume 48( Issue 23) pp:4109-4111
Publication Date(Web):
DOI:10.1002/anie.200900491
Co-reporter:DeborahL. Kays Dr.;Simon Aldridge Dr.
Angewandte Chemie 2009 Volume 121( Issue 23) pp:4172-4174
Publication Date(Web):
DOI:10.1002/ange.200900491
Co-reporter:Benjamin M. Gridley, Alexander J. Blake, Adrienne L. Davis, William Lewis, Graeme J. Moxey and Deborah L. Kays
Chemical Communications 2012 - vol. 48(Issue 71) pp:NaN8912-8912
Publication Date(Web):2012/07/20
DOI:10.1039/C2CC34525K
Cobalt(II) diaryl complexes react with CO to afford Co2(CO)8 and sterically encumbered ketones whose structure varies depending on the nature of the aryl ligands.
Co-reporter:Alexander J. Blake, William Lewis, Jonathan McMaster, Rhiannon S. Moorhouse, Graeme J. Moxey and Deborah L. Kays
Dalton Transactions 2011 - vol. 40(Issue 8) pp:NaN1645-1645
Publication Date(Web):2011/01/20
DOI:10.1039/C0DT01710H
The synthesis and characterisation of low-coordinate zinc and cadmium complexes of the sterically demanding 1,3,6,8-tetra-tert-butylcarbazol-9-yl ligand (tBu4carb−) are reported. (tBu4carb)2M (M = Zn 1; M = Cd 2) are the first examples of formally two-coordinate bis-carbazol-9-yl complexes of the Group 12 metals and 2 is the first crystallographically characterised two-coordinate amido complex of cadmium. The structure and bonding within these complexes are explored via a combination of X-ray crystallography and DFT calculations. The solid state structures for these zinc and cadmium complexes differ greatly from each other; not only do the steric demands of the peripheral tert-butyl substituents in these systems act to inhibit solvent coordination, but they also influence the coordination geometry around the metal centres.
Co-reporter:Mark A. Bradley, Chris Birchall, Alexander J. Blake, William Lewis, Graeme J. Moxey and Deborah L. Kays
Dalton Transactions 2017 - vol. 46(Issue 12) pp:NaN4110-4110
Publication Date(Web):2017/03/01
DOI:10.1039/C7DT00471K
The reactions between magnesium or zinc alkyls and 1,8-bis(triorganosilyl)diaminonaphthalenes afford the 1,8-bis(triorganosilyl)diamidonaphthalene complexes with elimination of alkanes. The reaction between 1,8-C10H6(NSiMePh2H)2 and one or two equivalents of MgnBu2 affords two complexes with differing coordination environments for the magnesium; the reaction between 1,8-C10H6(NSiMePh2H)2 and MgnBu2 in a 1:1 ratio affords 1,8-C10H6(NSiMePh2)2{Mg(THF)2} (1), which features a single magnesium centre bridging both ligand nitrogen donors, whilst treatment of 1,8-C10H6(NSiR3H)2 (R3 = MePh2, iPr3) with two equivalents of MgnBu2 affords the bimetallic complexes 1,8-C10H6(NSiR3)2{nBuMg(THF)}2 (R3 = MePh22, R3 = iPr33), which feature four-membered Mg2N2 rings. Similarly, 1,8-C10H6(NSiiPr3)2{MeMg(THF)}2 (4) and 1,8-C10H6(NSiMePh2)2{ZnMe}2 (5) are formed through reactions with the proligands and two equivalents of MMe2 (M = Mg, Zn). The reaction between 1,8-C10H6(NSiMePh2H)2 and two equivalents of MeMgX affords the bimetallic complexes 1,8-C10H6(NSiMePh2)2(XMgOEt2)2 (X = Br 6; X = I 7). Very small amounts of [1,8-C10H6(NSiMePh2)2{IMg(OEt2)}]2 (8), formed through the coupling of two diamidonaphthalene ligands at the 4-position with concomitant dearomatisation of one of the naphthyl arene rings, were also isolated from a solution of 7.
Co-reporter:Toby J. Blundell, Fiona R. Hastings, Benjamin M. Gridley, Graeme J. Moxey, William Lewis, Alexander J. Blake and Deborah L. Kays
Dalton Transactions 2014 - vol. 43(Issue 38) pp:NaN14264-14264
Publication Date(Web):2014/04/08
DOI:10.1039/C4DT00647J
Three m-terphenyl ligands 2,6-Ar2C6H3− [Ar = 2,6-Me2C6H3 (2,6-Xyl); 3,5-Me2C6H3 (3,5-Xyl); 2,3,4,5,6-Me5C6 (Pmp)] have been used to stabilise three series of two-coordinate Group 12 diaryl complexes; (2,6-Ar2C6H3)2M [M = Zn, Cd, Hg, Ar = 2,6-Xyl 1–3, 3,5-Xyl 4–6, Pmp 7–9], where differing steric demands on the metal centres are imparted. These are the first homoleptic d-block complexes featuring any of these ligands. Complexes 1–9 have been characterised in solution and the solid state; the analysis of structural changes produced by differences in ligand properties is reported. In particular, complexes 4–6 show smaller C–M–C bond angles and contain secondary ligand interactions that are not seen in the analogous complexes 1–3 and 7–9.
Co-reporter:Benjamin M. Gridley, Toby J. Blundell, Graeme J. Moxey, William Lewis, Alexander J. Blake and Deborah L. Kays
Chemical Communications 2013 - vol. 49(Issue 84) pp:NaN9754-9754
Publication Date(Web):2013/09/10
DOI:10.1039/C3CC46384B
The reaction between sterically demanding m-terphenyl lithiate complexes and cadmium dihalides yields unusual cubanes where changes in ligand bulk afford different formulations, in particular a rare heterodicubane structure.
Co-reporter:Graeme J. Moxey, Fabrizio Ortu, Leon Goldney Sidley, Helen N. Strandberg, Alexander J. Blake, William Lewis and Deborah L. Kays
Dalton Transactions 2014 - vol. 43(Issue 12) pp:NaN4846-4846
Publication Date(Web):2014/01/24
DOI:10.1039/C3DT53234H
Condensation reactions of carboxylic acids and anilines in the presence of polyphosphoric acid trimethylsilyl ester (PPSE) afforded a range of sterically demanding N,N′-bis(aryl)amidines, RN{C(R′)}N(H)R [R = Mes (Mes = 2,4,6-trimethylphenyl), R′ = Cy (Cy = cyclohexyl) L1H; R = Dipp (Dipp = 2,6-diisopropylphenyl), R′ = Cy L2H; R = Mes, R′ = Ph L3H; R = Dipp, R′ = Ph L4H; R = Mes, R′ = Dmp (Dmp = 3,5-dimethylphenyl) L5H; R = Dipp, R′ = Dmp L6H; R = Dmp, R′ = Cy L7H]. Amidines L1H–L7H have been characterised spectroscopically, and for L5H and L6H, by X-ray crystallography. Treatment of the amidines with di-n-butylmagnesium in THF solution afforded the monomeric magnesium bis(amidinates) [Mg(L1)2(THF)] 1, [Mg(L2)2] 2, [Mg(L3)2(THF)] 3, [Mg(L5)2(THF)] 5, [Mg(L6)2] 6, [Mg(L7)2] 7, and the magnesium mono(amidinate) complex [Mg(L4)(nBu)] 4. These complexes have been characterised spectroscopically, with 1–3, 5 and 6 also being structurally authenticated. Comparison of the magnesium bis(amidinate) complexes reveals that the steric bulk of the amidinate ligand influences both the solid state structure and solution behaviour of these complexes.
Co-reporter:Helen R. Sharpe, Ana M. Geer, Huw E. L. Williams, Toby J. Blundell, William Lewis, Alexander J. Blake and Deborah L. Kays
Chemical Communications 2017 - vol. 53(Issue 5) pp:NaN940-940
Publication Date(Web):2016/12/16
DOI:10.1039/C6CC07243G
Two- and three-coordinate m-terphenyl complexes of manganese and iron are efficient catalysts for the selective cyclotrimerisation of primary aliphatic isocyanates affording isocyanurates in short reaction times and under mild conditions.
Co-reporter:Victoria J. Richards, Alexandra L. Gower, Jasper E. H. B. Smith, E. Stephen Davies, Dorothée Lahaye, Anna G. Slater, William Lewis, Alexander J. Blake, Neil R. Champness and Deborah L. Kays
Chemical Communications 2012 - vol. 48(Issue 12) pp:NaN1753-1753
Publication Date(Web):2012/01/03
DOI:10.1039/C2CC16047A
The redox processes associated with BODIPY analogues are studied by electrochemical and spectroscopic methods revealing a characteristic profile for the persistent BODIPY radical and quenching of fluorescence upon reduction.
![Benzenecarboximidamide, N,N'-bis[2,6-bis(1-methylethyl)phenyl]-](http://img.cochemist.com/ccimg/220400/220357-34-6.png)
![Benzenecarboximidamide, N,N'-bis[2,6-bis(1-methylethyl)phenyl]-](http://img.cochemist.com/ccimg/220400/220357-34-6_b.png)
