Galerie Titelbilder

Galerie Titelbilder

[205] Front cover: Aminoalkylferrocenyldichlorophosphanes: Facile Synthesis for Versatile Chiral Starting Materials
Novel racemic and enantiomerically pure aminoalkylferrocenyldichlorophosphanes can be used as starting materials for the corresponding primary ferrocenylphosphanes, one of which was dilithiated to give an enantiomerically pure lithium–phosphorus closo cluster compound.

 

[220] Front cover: Different Transmetallation Behaviour of [M(P4HR4)] Salts toward Rhodium(I) and Copper(I) (M = Na, K; R = Ph, Mes; Mes = 2,4,6‐Me3C6H2)
The complexes [Rh(P4HMes4)(cod)] (3), [Rh2(μ‐P2HMes2)(μ‐PHMes)(cod)2] (4) and [Cu4(P4Ph4)2 (PH2Ph)2(PCyp3)2] (7) were obtained from the reaction of the monoanion (P4HR4)− and the corresponding rhodium or copper starting material. The complexes were characterised by multinuclear NMR spectroscopy and by X‐ray diffraction studies.

[245] Front cover: Hydrogen‐bonded pillars of alternating chiral complex cations and anions: 1. Synthesis, characterization, X‐ray structure and thermal stability of catena‐{[Co(H2oxado)3][Cr(C2O4)3]∙5H2O} and of its precursor (H3oxado)[Co(H2oxado)3](SO4)2∙2H2O
The salt {[Co(H2oxado)3][Cr(C2O4)3]·5H2O} (2) is formed readily from {Ba6(H2O)17[Cr(C2O4)3]4·7H2O} and (H3oxado)[Co(H2oxado)3](SO4)2·2H2O (1) in water. 2 forms a pillared nanochannel lattice encapsulating water molecules.

[306] Back cover: Carbaborane-Substituted 1,2-Diphosphetanes
Endocyclic P−P bonds are found in carbaborane‐substituted 1,2‐diphosphetanes, which are obtained in high yield from diastereomeric mixtures of 1,2‐bis(chlorophosphanyl)‐1,2‐dicarba-closo‐dodecaboranes(12). In their Communication on page 4701 ff., E. Hey‐Hawkins and coworkers show that the air‐ and water‐stable racemic 1,2‐diphosphetane depicted undergoes a ring‐opening reaction with elemental iodine to give exclusively rac‐1,2‐bis(iodo‐tertbutyl-phosphanyl)‐1,2‐dicarba‐closo‐dodecaborane(12).

[327] Front cover: Synthesis and Thermolysis of the Phosphorus‐Rich Manganese(I) Complex [Mn2(μ‐Br){cyclo‐(P4tBu3)PtBu}(CO)6]: From Complexes to Metal Phosphides
The cover picture shows the thermolysis (up to 1000°C) of the first phosphorus‐rich manganese(I) complex [Mn2(μ‐Br){cyclo‐(P4tBu3)PtBu}(CO)6] with formation of antiferromagnetic (below 103 K) Mn2P as the final product via a phosphorus‐rich phase (calculated as Mn2P5) at 315 °C. In their Full Paper on page 341 ff., E. Hey‐Hawkins et al. describe the synthesis of the molecular precursor from Na[cyclo‐(P5tBu4)] and [MnBr(CO)5]. The rearrangement of [cyclo‐(P5tBu4)] into [cyclo‐(P4tBu3)PtBu] was rationalized by theoretical studies.

[369] Inside front cover: Reduction of hydroxy-functionalised carbaboranyl carboxylic acids to tertiary alcohols by organolithium reagents
Reduction of hydroxy‐functionalised carbaboranyl carboxylic acids by organolithium reagents yields tertiary alcohols, while reaction of unsubstituted carbaboranyl carboxylic acids leads to cleavage of the exo‐polyhedral C–C bond.

[379] Front cover: P-chiral phosphorus heterocycles: a straightforward synthesis
A straightforward synthesis of P‐chiral polycyclic 7‐phospha‐norbornenes via an asymmetric Diels–Alder reaction is presented.

[382] Back cover: The first depleted heterojunction TiO2–MOF-based solar cell
A single‐step hydrothermal synthesis of a TiO2–Mil‐125 composite was applied for the first time to produce a depleted perovskite/TiO2–MOF heterojunction solar cell with 6.4% power conversion efficiency.

[389] Inside Back Cover: Redox Control of a Dendritic Ferrocenyl‐Based Homogeneous Catalyst
A redox‐switchable RuII catalyst featuring a dendritic ferrocenylphosphane ligand was developed. In their Communication on page 311 ff., E. Hey‐Hawkins et al. show that electronic communication between the redox‐active unit and the catalytic center allows the catalyst to be reversibly switched off and on through chemical oxidation and reduction. Such redox control could facilitate the development of catalysts with orthogonal activity for different substrates.

[393] Inside front cover. Carbaborane-based alkynylphosphanes and phospholes
1,2-Bis(N,N-dimethyl-aminochlorophosphanyl)-1,2-dicarba-closo-dodecaborane(12) reacts with lithiated phenylacetylene to give a carbaboranyl-based phosphane, while alkynylchloro-phosphanes and dilithiated carbaborane give bis(alkynylphosphanyl)carbaboranes.

 

 

 

[408] Inside front cover: Heterobimetallic complexes with highly flexible 1,1’-bis(phospholanoalkyl)ferrocene ligands
Flexible 1,1′-bis(phospholanoalkyl)ferrocenes react selectively with platinum(II), gold(I) and rhodium(I) to give macrocyclic chelate complexes.

[413] Front cover: nido-Dicarbaborate Induces Potent and Selective Inhibition of Cyclooxygenase-2
The front cover picture shows the pronounced impact of a nido‐dicarbaborate cluster on the binding mode of a cyclooxygenase (COX) inhibitor. The commercially available COX‐1‐selective inhibitor indomethacin was converted to a highly potent and selective inhibitor (nido‐indoborin) of the pathogenic isoform COX‐2 by replacing the chlorophenyl ring with a boron cluster. Introduction of the cluster leads to a binding mode in the COX‐2 site in which the indole moiety is flipped, compared with the orientation of indomethacin. Remarkably, the cluster opens up a subpocket by causing rotation of a leucine residue. The nido cluster is a promising pharmacophore and increases the stability and solubility of the inhibitor. More information can be found in the Communication by Evamarie Hey‐Hawkins et al. on page 175 in Issue 2, 2016.

[414] P-chiral 1-phosphanorbornenes: From asymmetric Phospha-Diels–Alder reactions towards ligand design and functionalization
A building set for chiral phosphorus. The principle of stereotopic face differentiation is successfully applied to a P=C bond. A divergent ligand synthesis is feasible after reduction of the chiral auxiliary.

[416] Inside cover: Formation of a Carbene-Phosphinidene Adduct by N-Heterocyclic Carbene-Induced P-P Bond Cleavage in Sodium Tetramesityltetraphosphanediide
The inside cover picture shows the attempt to stabilize the highly reactive tetramesityltetraphosphanediide anion (P4Mes42–, Mes = 2,4,6‐Me3C6H2) by adduct formation with an N‐heterocyclic carbene (NHC). However, rather than forming the expected stable adduct, the attack of the NHCs rips the tetraphosphane-diide chain apart to produce two neutral carbene–phosphinidenes and a P2Mes22– dianion, which is not “trapped” with NHC. Details are discussed in the Communication by E. Hey‐Hawkins et al. on p. 620 ff.

[418] Back cover: Charge-compensated metallacarborane building blocks for conjugation with peptides
The back cover picture shows the selective internalisation of a novel imidazolium‐based charge‐compensated cobalt bis(dicarbollide) derivative conjugated to the Y1 receptor‐selective derivative of neuropeptide Y, [F7,P34]‐NPY. Receptor internalisation occurred within the same range as that observed for [F7,P34]‐NPY. These observations indicate that such conjugated peptides are promising candidates as boron‐delivering agents for boron neutron capture therapy (BNCT). More information can be found in the full paper by A. G. Beck‐Sickinger, E. Hey‐Hawkins et al. on page 308 in Issue 4, 2016.

[421] Inside front cover: Selective Formation of Silver(I) Bis‐phospholane Macrocycles and Further Evidence that Gold(I) is Smaller than Silver(I)
Highly flexible bis‐phospholane ligands form 16‐ to 28‐membered dinuclear macrocyclic silver(I) complexes selectively without using high‐dilution techniques. Comparison with gold(I) complexes gives further evidence that gold(I) is significantly smaller than silver(I).

[429] Back cover: Planar‐Chiral Secondary Ferrocenylphosphanes
This cover feature shows a diastereomerically pure planar‐chiral secondary ferrocenylphosphane derived from Ugi's amine against a background depicting the Head of Janus, a symbol for the two different features of these compounds: They find application as chiral ligands for metal complexes in asymmetric catalysis, and the corresponding phosphinoborane derivatives could be suitable precursors for the synthesis of chiral P–B polymers by dehydrocoupling. Details are discussed in the article by E. Hey‐Hawkins et al. on page 256 ff.

[436] Front cover: Carboranes as Aryl Mimetics in Catalysis: A Highly Active Zwitterionic NHC‐Precatalyst
A new offspring of the organocatalyst family has hatched from the merger of covalent catalysis and a carborane as an aryl‐mimetic replacement: the novel zwitterionic triazolium based N‐heterocyclic carbene (NHC) precatalyst bears a 7,8‐dicarba‐nido‐undeca-boranyl substituent (nidus (lat.)=nest) and offers excellent activity and broad applicability in a wide range of organocatalytic transformations. The straightforward synthesis and a detailed comparison to recent aryl‐based precatalysts provides useful insights to pave the way for further development of this unprecedented class of catalysts. More information can be found in the Full Paper by K. Zeitler et al. on page 7932.

[441] Front cover: Basicity of N‐(Tetramesityltetraphospha-cyclopentylidene)cyclohexylamine: An Unusual Diphospha(III)guanidine Derivative
The Front Cover shows the pKa value of the unusual cyclic hetero‐oligophosphane cyclo‐P4Mes4C(NCy), whose C–N double bond does not exhibit the reactivity expected for imines, but can in fact be regarded as part of a substituted diphospha(III)guanidine moiety. According to quantum mechanical calculations, its basicity is comparable to that of methyl‐substituted monophospha(III)guanidine. Thus, the nitrogen atom can be protonated with HCl or HBF4. The pKa value of cyclo‐P4Mes4C(NCy) was measured by reactions with so‐called indicator bases and is in the range 4.9–5.2 in THF. More information can be found in the Full Paper by E. Hey‐Hawkins et al. For more on the story behind the cover research, see the Cover Profile.

[447] Inside back cover: Supramolecular self‐assembly of heterobimetallic complexes: a new N,P‐based, selective heteroditopic ligand
Pyrimidine‐hydrazone and phosphole architectures have been combined to create a new heteroditopic ligand capable of forming heterobimetallic ZnII/PdII, PbII/PdII and CuII/PdII complexes in high yielding stepwise or one pot reactions.

[458] Front cover: The Self‐Assembly of AgI‐Containing Heterobimetallic Complexes with a Discriminatory N,P‐Based Heteroditopic Ligand
The Cover Feature shows the unusual heterobimetallic dimeric complexes that are produced when our heteroditopic ligand is reacted with AgI, AgI/ZnII, or AgI/PbII ions. Trying to use self‐assembly to form heterobimetallic complexes with AgI can sometimes be a gamble due to its promiscuous nature. However, the high discriminatory power of our ligand's pyrimidine‐hydrazone and phosphole based coordination pockets enables the reliable and efficient synthesis of these diverse complexes in one pot reactions. More information can be found in the Full Paper by D. J. Hutchinson and E. Hey‐Hawkins.

[459] Front cover: Carbaboranylation of Truncated C‐Terminal Neuropeptide Y Analogue Leads to Full hY1 Receptor Agonism
The front cover picture shows the C‐terminal part of neuropeptide Y, which is N‐terminally modified with a carbaborane cluster (hammer) that can activate and internalize its cognate G protein‐coupled receptor hY1R (cylindric shape) into the cell (shape‐sorter toy). hY1R is of high therapeutic interest as it is involved in a number of pathologies like obesity or cancer. Therefore, truncated NPY analogues are desirable for use as drugs against these conditions. However, C‐terminal fragments of NPY often end up being antagonists or very weak, partial agonists that solely induce G protein signalling but no internalization, a prerequisite for, for example, drug shuttle systems. We discovered that substitution of the N terminus of such a fragment with a lysine carrying a bulky, hydrophobic moiety like a carbaborane leads to full hY1R selective agonism and most importantly induces internalization. More information can be found in the full paper by K. Bellmann‐Sickert et al. on page 2300 in Issue 21, 2018.

[462] Front cover: Exploiting the Ring Strain of Diphosphetanes: A Synthetic and Computational Approach towards 1,2,5‐Selenadiphospholanes
The front cover shows two pots on a crowded table planted with bulky tert‐butyl groups symbolizing the phosphorus atoms in the strained ring system of a carborane‐substituted 1,2‐diphosphetane. Facilitated by the ring strain of this cyclic moiety, selenium can be inserted into the P−P bond as indicated by the hanging plant. Details are given in the Full Paper by E. Hey‐Hawkins and co‐workers on page 1057 in Issue 11, 2018.

[469] Front cover: Carboranyl Analogues of Celecoxib with Potent Cytostatic Activity against Human Melanoma and Colon Cancer Cell Lines
The Cover Feature shows carboranyl analogues of celecoxib, a potent COX‐2‐selective inhibitor (COXIB). Cyclooxygenase‐2 (COX‐2) has a prominent role in the occurrence and progression of various cancers. Recently, there is an expressed focus on the development of new COX‐2‐selective inhibitors (COXIBs) as potential cytostatic agents. A highly stable carborane cluster, which can serve as phenyl mimetic, was implemented in the structure of celecoxib in order to generate analogues with enhanced metabolic stability. Although the new derivatives do not act as COXIBs, they proved to have a potent cytostatic effect on various melanoma and colon cancer cell lines. Cover illustration by Menyhárt‐Botond Sárosi. More information can be found in the Full Paper by Evamarie Hey‐Hawkins et al. on page 315 in Issue 3, 2019.

[475] Inside front cover: Molecular doping: accessing the first carborane‐substituted 1,2,3‐triphospholanide via insertion of P− into a P−P bond
Insertion of a P− anion into a P–P bond yielding the first carborane‐substituted 1,2,3‐ triphospholanide 1 was achieved by treating a carborane‐substitued 1,2‐diphosphetane with sodium phosphaethynolate.

[482] Inside back cover: Modular triazine‐based carborane‐containing carboxylic acids – synthesis and characterisation of potential boron neutron capture therapy agents made of readily accessible building blocks
Boron‐rich carboxylic acid derivatives were synthesised as coupling partners for tumour‐selective
biomolecules with applications as selective BNCT agents.

[483] Inside front cover: Accessing the First nido‐Carborane‐Substituted Diphosphetane: A Ligand and Synthon for nido‐Carboranylphosphanes
nido‐Carboranes are valuable backbones for the development of phosphorus‐based ligands. The cover, designed by Dr. Christoph Selg (Leipzig University), shows a highlight of the present study: Cu2I2 units bridged by the first nido‐carborane‐substituted diphosphetane, as symbolised by the crabs, forming a one‐dimensional coordination polymer. The diphosphetane is also suitable for functionalization to unprecedented nido‐carborane‐based P,N ligands. More information can be found in the Full Paper by E. Hey‐Hawkins et al. on page 11456.

[489] Front cover: Enlargement of a Modular System—Synthesis and Characterization of an s-Triazine-Based Carboxylic Acid Ester Bearing a Galactopyranosyl Moiety and an Enormous Boron Load
The amount of boron accumulated in tumor tissue plays an important role regarding the success of the boron neutron capture therapy (BNCT). In this article, we report a modular system, combining readily available starting materials, like glycine, 1,3,5-triazine and the well-known 9-mercapto-1,7-dicarba-closo-dodecaborane(12), as well as α--galactopyranose for increased hydrophilicity, with a novel boron-rich tris-meta-carboranyl thiol.

[496] Back cover: Tuning a modular system – synthesis and characterisation of a boron‐rich s‐triazine-based carboxylic acid and amine bearing a galactopyranosyl moiety
Introduction of a galactopyranosyl moiety in s‐triazine‐based boron‐rich carboxylic acids and amines results in soluble and suitable coupling partners for tumour‐selective biomolecules with applications in boron neutron capture therapy (BNCT).

Wiley celebrated the International Year of the Periodic Table with an interactive Periodic Table of books devoted to each one of the elements! In the case of Boron, the featured book is "Boron-Based Compounds: Potential and Emerging Applications in Medicine" edited by Evamarie Hey-Hawkins and Clara Viñas Teixidor.

[501] Back Cover: Unexpected Isomerization of Hexa‐tert‐butyl‐octaphosphane
The vitruvian phosphane is presented! Just as da Vinci's drawing, it shows two superimposed phosphane molecules and thus a conflation of both phosphorus frameworks. Similar to their isolobal organic relatives, these isomers of hexa‐tert‐butyl‐octaphosphane interconvert, which is represented herein by a rotation of 90°, keeping the two central P atoms fixed. The new phosphorus‐rich molecule with pentalane structure coordinates to gold(I) or palladium(II) with different coordination modes. The beauty that lies in these structures is a reminder of da Vinci's masterpiece. More information can be found in the Communication by E. Hey‐Hawkins and T. Grell on page 1008.

[502] Front cover: Dynamic Gold(I) Complexes of Hexa‐tert‐butyl‐octaphosphane
The Front Cover shows a huge octopus wrecking a ship. Be on your guard! Like a shadow from the depths of the ocean arises the monstrous OCTAPhosphane from the almost forgotten realm of phosphorus‐rich compounds. An ancient molecule with eight directly connected phosphorus atoms and an unquenchable thirst for coordination that devours gold(I) atoms like the octopus an unsuspecting ship. But do not grieve, from the merciless attack emerge magnificent complexes which show an unusual coordination mode of the gold(I) atoms that, in combination with the flexibility of the ligand, leads to a fascinating dynamic behavior in solution (cover design adapted from original public domain image https://hu.wikipedia.org/wiki/F%C3%A1jl:Pierre_Denys_de_Montfort_ske6.jpg). More information can be found in the Communication by T. Grell and E. Hey‐Hawkins. For more on the story behind the cover research, see the Cover Profile.

[503] Inside cover: Anilate Tethered Neutral Tetrahedral Pd(II) Cages Exhibiting Selective Encapsulation of Xylenes and Mesitylene
Neutral molecular cages with definite intrinsic voids and adjustable portals are fascinating for the selective encapsulation and recognition of organic guest molecules. This work reports a family of iso‐structural neutral tetrahedral Pd(II) derived cages built from three different anilate linkers that show the selective encapsulation of xylene isomers and mesitylene. The selective binding of these aromatic guests is driven by the variations in the portal diameters controlled by the substituents on the anilate backbone and their interactions with guest molecules. More information can be found in the Communication by R. Boomishankar et al. on page 4209.

[507] Front Cover: Tricoordinate Coinage Metal Complexes with a Redox‐Active Tris‐(Ferrocenyl)triazine Backbone Feature Triazine–Metal Interactions
The power of three ferrocenes: all three coinage metal ions are held atop the triazine core of a novel C3‐symmetric tris‐phosphane. Despite nearly identical solid‐state structures featuring unusual interactions between s‐triazine and the metal ions, solution‐state behaviour of the complexes differs. Variable‐temperature NMR spectroscopy and spectroelectrochemistry aided the understanding of these intriguing compounds, in particular regarding their rich electro-chemistry, and inspired Christoph Selg to create this cover picture. More information can be found in the Communication by E. Hey‐Hawkins et al. on page 5758. Cover profile.

[509] Front cover: Versatile Coordination Chemistry of Hexa-tert-Butyl-Octaphosphine
The octaphosphine {cyclo-(P4tBu3)}2 (1) possesses a multifaceted coordination chemistry. The predominant binding mode is a P,P-chelate, e.g., in the monometallic chelate complex [MLL′(12P2,P4′)] in which the ligand 1 adopts a gauche conformation. Examples include square-planar (M = RhI, L = CO, L′ = Cl (2), M = PdII, L = L′ = Cl (3), M = PtII, L = L′ = Cl (9)), tetrahedral (M = Co–I, L = NO, L′ = CO (4)), and trigonal-planar complexes [ML(12P2,P4′)] (M = Pd0, L = PPh3, (5), M = CuI, L = Br (6)). With 2 equiv of [CuBr(SMe2)], a dinuclear complex [(CuBr)2(12P2,P2′2P4,P4′)] (7) was obtained which features a synperiplanar conformation of the octaphosphine. A second coordination mode was also observed in [PtCl2(12P1,P2′)] (10) in which the bridge phosphorus atom in octaphosphine 1 is involved in the chelation, with the ligand in an antiperiplanar conformation. Thermolysis of selected complexes showed them to be suitable candidates for the generation of phosphorus-rich metal phosphides MPx (x > 1).

letzte Änderung: 08.10.2020