Acta Crystallographica Section a Foundations of Crystallography, Aug 1, 2006
Recently the funding councils in the UK stated that 'the data underpinning the publi... more Recently the funding councils in the UK stated that 'the data underpinning the published results of publically-funded research should be made available as widely and rapidly as possible'. Thirty years ago a research student would present about five crystal structures as their PhD thesis, however with modern technologies and good crystals this can now be achieved in the timespan of a single morning. This increase in pace of generation further exacerbates a problem in the communication of the results. Additionally, the general route ...
A series of compounds of the N3P3Cl(6-n)(NHBu t )n family (where n = 0, 1, 2, 4 and 6) are presen... more A series of compounds of the N3P3Cl(6-n)(NHBu t )n family (where n = 0, 1, 2, 4 and 6) are presented and their molecular parameters are related to trends in physical properties, which provides insight into a potential reaction mechanism for nucleophilic substitution. The crystal structures of N3P3Cl5(NHBu t ) and N3P3Cl2(NHBu t )4 have been determined at 120K and
Reation of [WI2(CO)(NCMe)(η2-PhC2Ph)2] with an equimolar quantity of MeS(CH2)2S(CH2)2SMe in CH2Cl... more Reation of [WI2(CO)(NCMe)(η2-PhC2Ph)2] with an equimolar quantity of MeS(CH2)2S(CH2)2SMe in CH2Cl2 at room temperature gave the complex [WI2(CO){(Me)S(CH2)2S(CH2)2SMe-S,S′}(η2-PhC2Ph)] (1). The crystal structure of 1 shows the MeS(CH2)2S(CH2)2SMe ligand attached to the tungsten via two adjacent sulphur atoms, leaving the third sulphur atom uncoordinated. Preliminary studies of the reactions of 1 are also described.
1,1′-Ferrocene biscarboxaldehyde (1) has been prepared and the aldehyde groups were subsequently ... more 1,1′-Ferrocene biscarboxaldehyde (1) has been prepared and the aldehyde groups were subsequently protected with acetal groups to produce 1,1′-bisacetalferrocene (2). A ring-locked ferrocene was synthesised by further derivatisation of the cyclopentadiene rings at the 2,2′ positions with phosphine substituents to produce 2,2′-bis-(acetal)-1,1′-diphenylphosphinoferrocene (3), which was subsequently coordinated to either a nickel chloride (5) or nickel bromide (6) metal centre. The
ABSTRACT In an attempt to build up borane-based multicluster assemblies, thermolysis of [6,9-(SMe... more ABSTRACT In an attempt to build up borane-based multicluster assemblies, thermolysis of [6,9-(SMe2)2-arachno-B10H12] 1 in inert hydrocarbon solution, followed by chromatographic separation, has resulted in the isolation not only of the previously established single-cluster product from this reaction, [5-(SMe2)-nido-B10H12] 2 (30%), but also the two two-cluster species [6,9-(SMe2)2-arachno-B10H11-1-(6-nido-B10H13)] 3 (20%) and [1,6-(nido-B10H13)2] 6 (ca. 0.5%) and the two three-cluster species [6,9-(SMe2)2-arachno-B10H10-1,5-(6-nido-B10H13)2] 4 (5%), characterized crystallographically, and [6,9-(SMe2)2-arachno-B10H10-1,3-(6-nido-B10H13)2] 5 (<1%), identified by NMR spectroscopy. An improved crystallographic investigation of [5-(SMe2)-nido-B10H12] 2 is also presented. The feasibility of the stability of species resulting from multiple adjacent substitution of nido-decaboranyl units on the [6,9-(SMe2)2-arachno-B10H12] skeleton is tested by DFT calculations. In an extension, to attempt the use of pre--linked two-cluster compounds as starting substrates, two-cluster [5-(SMe2)-4-(2-nido-B10H13)-nido-B10H11] 7 (0.6%) has been isolated from the reaction of SMe2 with [1,5-(nido-B10H13)2], other identified products being compound 1 (39%) and compound 3 (10.5%).
ABSTRACT Dinuclear species containing iron centres linked via various bridging boryl ligands have... more ABSTRACT Dinuclear species containing iron centres linked via various bridging boryl ligands have been synthesised and a combination of crystallographic, computational and spectroscopic (Mössbauer, IR, Raman) techniques have been used to probe the bonding in these complexes.
Keplerates are molecules that contain metal polyhedra that describe both Platonic and Archimedean... more Keplerates are molecules that contain metal polyhedra that describe both Platonic and Archimedean solids; new copper Keplerates are reported, with physical studies indicating that even where very high molecular symmetry is found, the low temperature physics does not necessarily reflect this symmetry.
Dalton transactions (Cambridge, England : 2003), Jan 16, 2015
A family of Mn(III) dimers of general formula [Mn(R-sao)2(dpa)2](ClO4)2 () has been synthesised u... more A family of Mn(III) dimers of general formula [Mn(R-sao)2(dpa)2](ClO4)2 () has been synthesised using derivatised phenolic oximes (R-saoH2, where R = H, Me, Et, Ph) in combination with di-(2-picolyl)-amine (dpa). Their structures reveal a double-oxime bridged [Mn(III)(NO)]2 magnetic core in which the Jahn-Teller axes lie perpendicular to the bridging plane, in contrast to two previously reported family members (, ). The switch in the orientation of the Jahn-Teller axes is enforced through the use of the chelating ligand which is present in and absent in . Dc magnetic susceptibility measurements reveal that the exchange interactions between the Mn(III) metal centres in are antiferromagnetic in contrast to that observed for and which are ferromagnetic. DFT calculations performed on complexes reproduce both the sign and strength of the J values found experimentally. Molecular orbital analysis unlocks a common mechanism of magnetic coupling based upon the orientation of the Jahn-Teller ...
Acta Crystallographica Section a Foundations of Crystallography, Aug 1, 2006
Recently the funding councils in the UK stated that 'the data underpinning the publi... more Recently the funding councils in the UK stated that 'the data underpinning the published results of publically-funded research should be made available as widely and rapidly as possible'. Thirty years ago a research student would present about five crystal structures as their PhD thesis, however with modern technologies and good crystals this can now be achieved in the timespan of a single morning. This increase in pace of generation further exacerbates a problem in the communication of the results. Additionally, the general route ...
A series of compounds of the N3P3Cl(6-n)(NHBu t )n family (where n = 0, 1, 2, 4 and 6) are presen... more A series of compounds of the N3P3Cl(6-n)(NHBu t )n family (where n = 0, 1, 2, 4 and 6) are presented and their molecular parameters are related to trends in physical properties, which provides insight into a potential reaction mechanism for nucleophilic substitution. The crystal structures of N3P3Cl5(NHBu t ) and N3P3Cl2(NHBu t )4 have been determined at 120K and
Reation of [WI2(CO)(NCMe)(η2-PhC2Ph)2] with an equimolar quantity of MeS(CH2)2S(CH2)2SMe in CH2Cl... more Reation of [WI2(CO)(NCMe)(η2-PhC2Ph)2] with an equimolar quantity of MeS(CH2)2S(CH2)2SMe in CH2Cl2 at room temperature gave the complex [WI2(CO){(Me)S(CH2)2S(CH2)2SMe-S,S′}(η2-PhC2Ph)] (1). The crystal structure of 1 shows the MeS(CH2)2S(CH2)2SMe ligand attached to the tungsten via two adjacent sulphur atoms, leaving the third sulphur atom uncoordinated. Preliminary studies of the reactions of 1 are also described.
1,1′-Ferrocene biscarboxaldehyde (1) has been prepared and the aldehyde groups were subsequently ... more 1,1′-Ferrocene biscarboxaldehyde (1) has been prepared and the aldehyde groups were subsequently protected with acetal groups to produce 1,1′-bisacetalferrocene (2). A ring-locked ferrocene was synthesised by further derivatisation of the cyclopentadiene rings at the 2,2′ positions with phosphine substituents to produce 2,2′-bis-(acetal)-1,1′-diphenylphosphinoferrocene (3), which was subsequently coordinated to either a nickel chloride (5) or nickel bromide (6) metal centre. The
ABSTRACT In an attempt to build up borane-based multicluster assemblies, thermolysis of [6,9-(SMe... more ABSTRACT In an attempt to build up borane-based multicluster assemblies, thermolysis of [6,9-(SMe2)2-arachno-B10H12] 1 in inert hydrocarbon solution, followed by chromatographic separation, has resulted in the isolation not only of the previously established single-cluster product from this reaction, [5-(SMe2)-nido-B10H12] 2 (30%), but also the two two-cluster species [6,9-(SMe2)2-arachno-B10H11-1-(6-nido-B10H13)] 3 (20%) and [1,6-(nido-B10H13)2] 6 (ca. 0.5%) and the two three-cluster species [6,9-(SMe2)2-arachno-B10H10-1,5-(6-nido-B10H13)2] 4 (5%), characterized crystallographically, and [6,9-(SMe2)2-arachno-B10H10-1,3-(6-nido-B10H13)2] 5 (<1%), identified by NMR spectroscopy. An improved crystallographic investigation of [5-(SMe2)-nido-B10H12] 2 is also presented. The feasibility of the stability of species resulting from multiple adjacent substitution of nido-decaboranyl units on the [6,9-(SMe2)2-arachno-B10H12] skeleton is tested by DFT calculations. In an extension, to attempt the use of pre--linked two-cluster compounds as starting substrates, two-cluster [5-(SMe2)-4-(2-nido-B10H13)-nido-B10H11] 7 (0.6%) has been isolated from the reaction of SMe2 with [1,5-(nido-B10H13)2], other identified products being compound 1 (39%) and compound 3 (10.5%).
ABSTRACT Dinuclear species containing iron centres linked via various bridging boryl ligands have... more ABSTRACT Dinuclear species containing iron centres linked via various bridging boryl ligands have been synthesised and a combination of crystallographic, computational and spectroscopic (Mössbauer, IR, Raman) techniques have been used to probe the bonding in these complexes.
Keplerates are molecules that contain metal polyhedra that describe both Platonic and Archimedean... more Keplerates are molecules that contain metal polyhedra that describe both Platonic and Archimedean solids; new copper Keplerates are reported, with physical studies indicating that even where very high molecular symmetry is found, the low temperature physics does not necessarily reflect this symmetry.
Dalton transactions (Cambridge, England : 2003), Jan 16, 2015
A family of Mn(III) dimers of general formula [Mn(R-sao)2(dpa)2](ClO4)2 () has been synthesised u... more A family of Mn(III) dimers of general formula [Mn(R-sao)2(dpa)2](ClO4)2 () has been synthesised using derivatised phenolic oximes (R-saoH2, where R = H, Me, Et, Ph) in combination with di-(2-picolyl)-amine (dpa). Their structures reveal a double-oxime bridged [Mn(III)(NO)]2 magnetic core in which the Jahn-Teller axes lie perpendicular to the bridging plane, in contrast to two previously reported family members (, ). The switch in the orientation of the Jahn-Teller axes is enforced through the use of the chelating ligand which is present in and absent in . Dc magnetic susceptibility measurements reveal that the exchange interactions between the Mn(III) metal centres in are antiferromagnetic in contrast to that observed for and which are ferromagnetic. DFT calculations performed on complexes reproduce both the sign and strength of the J values found experimentally. Molecular orbital analysis unlocks a common mechanism of magnetic coupling based upon the orientation of the Jahn-Teller ...
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