Browse
Submit Data
Databases
API
Help

Dataset Information

9 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Synthesis of a carborane-substituted bis(phosphanido) cobaltate(i), ligand substitution, and unusual P₄ fragmentation.

ABSTRACT: Oxidative addition of the P-P single bond of an ortho-carborane-derived 1,2-diphosphetane (1,2-C₂(PMes)₂B₁₀H₁₀) (Mes = 2,4,6-Me₃C₆H₂) to cobalt(-i) and nickel(0) sources affords the first heteroleptic complexes of a carborane-bridged bis(phosphanido) ligand. The complexes also incorporate labile ligands suitable for further functionalisation. Thus, the cobalt(i) complex [K([18]crown-6)][Co{1,2-(PMes)₂C₂B₁₀H₁₀}(cod)] (cod = 1,5-cyclooctadiene) bearing a labile cyclooctadiene ligand undergoes facile ligand exchange reactions with isonitriles and tert-butyl phosphaalkyne with retention of the bis(phosphanido) ligand. However, in the reaction with one equivalent of P₄, the electron-rich bis(phosphanido) moiety abstracts a single phosphorus atom with formation of a new P₃ chain, while the remaining three P atoms derived from P₄ form an η³-coordinating cyclo-P₃ ligand. In contrast, when the same reaction is performed with two equivalents of the cobalt(i) complex, a dinuclear product is formed which features an unusual P₄ chain in its molecular structure.

SUBMITTER: Coburger P

PROVIDER: S-EPMC8386647 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Synthesis of 9-borafluorene analogues featuring a three-dimensional 1,1'-bis(o-carborane) backbone.

Project description:The synthesis of [1,1'-bis(o-carboranyl)]boranes was achieved through the deprotonation of 1,1'-bis(o-carborane) reagents followed by salt metathesis with (iPr)2NBCl2. X-ray crystallography confirms planar central BC4 rings and Gutmann-Beckett studies reveal an increase in Lewis acidity at the boron center in comparison to their biphenyl congener, 9-borafluorene.

| S-EPMC6624192 | biostudies-literature

Bis(2-methyl-anilinium) diaqua-bis[dihydrogendiphosphato(2-)]cobaltate(II).

Project description:In the title cobalt(II) complex with 2-methyl-anilinium and diphosphate, (C(7)H(10)N)(2)[Co(H(2)P(2)O(7))(2)(H(2)O)(2)], a three-dimensional network is built up from anionic layers of [Co(H(2)P(2)O(7))(2)(H(2)O)(2)](2-) units and 2-methyl-anilinium cations located between these layers. The dihydrogendiphosphate groups present a bent eclipsed conformation, while the Co(2+) ions lie on inversion centers. An intricate network of O-H?O and N-H?O hydrogen bonds is established between the different components, assuring the cohesion of the network with other inter-actions, being of electrostatic and van der Waals nature.

| S-EPMC2971134 | biostudies-literature

Bis(guanidinium) trans-diaqua-bis(malonato-?O,O')cobaltate(II).

Project description:In the title compound, (CH(6)N(3))(2)[Co(C(3)H(2)O(4))(2)(H(2)O)(2)], the anions lie on crystallographic centres of inversion. The crystal structure adopts a layered structure, stabilized by an extensive network of N-H?O and O-H?O hydrogen bonds. One H atom of the guanidinium cation does not participate in any strong hydrogen bonds.

| S-EPMC2915119 | biostudies-literature

Bis(triethyl-ammonium) tetra-chlorido-cobaltate(II).

Project description:The crystal structure of the title compound, (C(6)H(16)N)(2)[CoCl(4)], is comprised of a tetrahedral [CoCl(4)](2-) anion and two independent triethyl-ammonium cations. The latter are featureless while the [CoCl(4)](2-) anion exhibits typical Co-Cl bond lengths [2.2428?(15)-2.2847?(16)?Å] and a Cl-Co-Cl angular range of 107.58?(6)-112.73?(7)°. In the crystal, N-H?Cl hydrogen bonds between the two crystallographically independent cations and the [CoCl(4)](2-) anion generate discrete ion triplets. The two Co-Cl bonds involved in these inter-actions are slightly longer than the remaining two.

| S-EPMC3379194 | biostudies-literature

Changing the Reactivity of Zero- and Mono-Valent Germanium with a Redox Non-Innocent Bis(silylenyl)carborane Ligand.

Project description:Using the chelating C,C'-bis(silylenyl)-ortho-dicarborane ligand, 1,2-(RSi)2 -1,2-C2 B10 H10 [R=PhC(NtBu)2 ], leads to the monoatomic zero-valent Ge complex ("germylone") 3. The redox non-innocent character of the carborane scaffold has a drastic influence on the reactivity of 3 towards reductants and oxidants. Reduction of 3 with one molar equivalent of potassium naphthalenide (KC10 H8 ) causes facile oxidation of Ge0 to GeI along with a two-electron reduction of the C2 B10 cluster core and subsequent GeI -GeI coupling to form the dianionic bis(silylene)-supported Ge2 complex 4. In contrast, oxidation of 3 with one molar equivalent of [Cp2 Fe][B{C6 H3 (CF3 )2 }4 ] as a one-electron oxidant furnishes the dicationic bis(silylene)-supported Ge2 complex 5. The Ge0 atom in 3 acts as donor towards GeCl2 to form the trinuclear mixed-valent Ge0 →GeII ←Ge0 complex 6, from which dechlorination with KC10 H8 affords the neutral Ge2 complex 7 as a diradical species.

| S-EPMC8252802 | biostudies-literature

Design, synthesis, and antiprotozoal evaluation of new 2,4-bis[(substituted-aminomethyl)phenyl]quinoline, 1,3-bis[(substituted-aminomethyl)phenyl]isoquinoline and 2,4-bis[(substituted-aminomethyl)phenyl]quinazoline derivatives.

Project description:A series of new 2,4-bis[(substituted-aminomethyl)phenyl]quinoline, 1,3-bis[(substituted-aminomethyl)phenyl]isoquinoline, and 2,4-bis[(substituted-aminomethyl)phenyl]quinazoline derivatives was designed, synthesised, and evaluated in vitro against three protozoan parasites (Plasmodium falciparum, Leishmania donovani, and Trypanosoma brucei brucei). Biological results showed antiprotozoal activity with IC50 values in the µM range. In addition, the in vitro cytotoxicity of these original molecules was assessed with human HepG2 cells. The quinoline 1c was identified as the most potent antimalarial candidate with a ratio of cytotoxic to antiparasitic activities of 97 against the P. falciparum CQ-sensitive strain 3D7. The quinazoline 3h was also identified as the most potent trypanosomal candidate with a selectivity index (SI) of 43 on T. brucei brucei strain. Moreover, as the telomeres of the parasites P. falciparum and Trypanosoma are possible targets of this kind of nitrogen heterocyclic compounds, we have also investigated stabilisation of the Plasmodium and Trypanosoma telomeric G-quadruplexes by our best compounds through FRET melting assays.

| S-EPMC6968685 | biostudies-literature

Bis(4-amino-pyridinium) tetra-chlorido-cobaltate(II).

Project description:In the title compound, (C(5)H(7)N(2))(2)[CoCl(4)], the cobalt(II) ion is coordinated by four chloride ions in a slightly distorted tetra-hedral geometry. The crystal packing is stabilized by inter-molecular N-H?Cl hydrogen bonding, forming a three-dimensional network. The crystal was a non-merohedral twin emulating tetra-gonal symmetry, but being in fact ortho-rhom-bic.

| S-EPMC2977578 | biostudies-literature

Design of substituted bis-Tetrahydrofuran (bis-THF)-derived Potent HIV-1 Protease Inhibitors, Protein-ligand X-ray Structure, and Convenient Syntheses of bis-THF and Substituted bis-THF Ligands.

Project description:We investigated substituted bis-THF-derived HIV-1 protease inhibitors in order to enhance ligand-binding site interactions in the HIV-1 protease active site. In this context, we have carried out convenient syntheses of optically active bis-THF and C4-substituted bis-THF ligands using a [2,3]-sigmatropic rearrangement as the key step. The synthesis provided convenient access to a number of substituted bis-THF derivatives. Incorporation of these ligands led to a series of potent HIV-1 protease inhibitors. Inhibitor 23c turned out to be the most potent (K(i) = 2.9 pM; IC(50) = 2.4 nM) among the inhibitors. An X-ray structure of 23c-bound HIV-1 protease showed extensive interactions of the inhibitor with the protease active site, including a unique water-mediated hydrogen bond to the Gly-48 amide NH in the S2 site.

| S-EPMC3325757 | biostudies-literature

Efficient synthesis of 5-substituted 2-aryl-6-cyanoindolizines via nucleophilic substitution reactions.

Project description:2-Aryl-6-cyano-7-methyl-5-indolizinones were successfully converted into 2-aryl-5-chloro-6-cyano-7-methylindolizines. The obtained 5-chloroindolizines readily underwent nucleophilic substitution at position 5 leading in high yields to novel 5-functionalised indolizines.

| S-EPMC1399457 | biostudies-literature

Unusual fragmentation pathways in collagen glycopeptides.

Project description:Collagens are the most abundant glycoproteins in the body. One characteristic of this protein family is that the amino acid sequence consists of repeats of three amino acids -(X-Y-Gly)n. Within this motif, the Y residue is often 4-hydroxyproline (HyP) or 5-hydroxylysine (HyK). Glycosylation in collagen occurs at the 5-OH group in HyK in the form of two glycosides, galactosylhydroxylysine (Gal-HyK) and glucosyl galactosylhydroxylysine (GlcGal-HyK). In collision induced dissociation (CID), collagen tryptic glycopeptides exhibit unexpected gas-phase dissociation behavior compared to typical N- and O-linked glycopeptides (i.e., in addition to glycosidic bond cleavages, extensive cleavages of the amide bonds are observed). The Gal- or GlcGal- glycan modifications are largely retained on the fragment ions. These features enable unambiguous determination of the amino acid sequence of collagen glycopeptides and the location of the glycosylation site. This dissociation pattern was consistent for all analyzed collagen glycopeptides, regardless of their length or amino acid composition, collagen type or tissue. The two fragmentation pathways-amide bond and glycosidic bond cleavage-are highly competitive in collagen tryptic glycopeptides. The number of ionizing protons relative to the number of basic sites (i.e., Arg, Lys, HyK, and N-terminus) is a major driving force of the fragmentation. We present here our experimental results and employ quantum mechanics calculations to understand the factors enhancing the labile character of the amide bonds and the stability of hydroxylysine glycosides in gas phase dissociation of collagen glycopeptides.

| S-EPMC3679267 | biostudies-literature