Browse
Submit Data
Databases
API
Help

Dataset Information

14 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Divergent Reactivity of an Isolable Nickelacyclobutane.

ABSTRACT: Nickelacyclobutanes are mostly invoked as reactive intermediates in the reaction of nickel carbenes and olefins to yield cyclopropanes. Nevertheless, early work suggested that other decomposition routes such as β-hydride elimination and even metathesis could be accessible. Herein, we report the isolation and characterization of a stable pentacoordinated nickelacyclobutane incorporated in a pincer complex. The coordination of different coligands to the nickelacyclobutane determines its selective decomposition along cyclopropanation, metathesis or apparent β-hydride elimination pathways. DFT calculations shed light on the mechanism of these different pathways.

SUBMITTER: Sansores-Paredes MLG

PROVIDER: S-EPMC9298726 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

An Isolable Three-Coordinate Germanone and Its Reactivity.

Project description:A rare three-coordinate germanone [IPrN]2 Ge=O (IPrN=bis(2,6-diisopropylphenyl)imidazolin-2-imino) was successfully isolated. The germanone has a rather high thermal stability in arene solvent, and no detectable change was observed at 80 °C for at least one week. However, high thermal stability of [IPrN]2 Ge=O does not prevent its reactivity toward small molecules. Structural analysis and initial reactivity studies revealed the highly polarized nature of the terminal Ge=O bond. Besides, the addition of phenylacetylene, as well as O-atom transfer with 2,6-dimethylphenyl isocyanide make it a mimic of nucleophilic transition-metal oxides. Mechanism for O-atom transfer reaction was investigated via DFT calculations, which revealed that the reaction proceeds via a [2+2] cycloaddition intermediate.

| S-EPMC9292218 | biostudies-literature

Isolable iodosylarene and iodoxyarene adducts of Co and their O-atom transfer and C-H activation reactivity.

Project description:We report an unusual series of discrete iodosyl- and iodoxyarene adducts of Co. The formation of these adducts was confirmed by a suite of techniques including single crystal X-ray diffraction. The reactivity of these adducts with O-atom acceptors and an H-atom donor has been investigated with particular focus on elucidating mechanistic details. Detailed kinetic analysis allows for discrimination between proposed oxo and adduct mediated mechanisms. In particular, these reactions have been interrogated by competition experiments with isotopically labelled mixtures which shows that all of the studied adducts display a large KIE. These studies suggest different mechanisms may be relevant depending on subtle substituent changes in the adduct complexes. Reactivity data are consistent with the involvement of a transient oxo complex in one case, while the two other systems appear to react with substrates directly as iodosyl- or iodoxyarene adducts. These results support that reactivity typically ascribed to metal-oxo complexes, such as O-atom transfer and C-H activation, can also be mediated by discrete transition metal iodosyl- or iodoxyarene adducts that are frequent intermediates in the generation of oxo complexes. The influence of additional Lewis acids such as Sc3+ on the reactivity of these systems has also been investigated.

| S-EPMC5958341 | biostudies-literature

Divergent transcriptional regulation of astrocyte reactivity across disorders

Project description:This SuperSeries is composed of the SubSeries listed below.

2022-05-26 | GSE199482 | GEO

Isolable Diaminophosphide Boranes.

Project description:Metalation of secondary diaminophosphine boranes by alkali metal amides provides a robust and selective access route to a range of metal diaminophosphide boranes M[(R2 N)2 P(BH3 )] (M=Li, Na, K; R=alkyl, aryl) with acyclic or heterocyclic molecular backbones, whereas reduction of a chlorodiaminophosphine borane gave less satisfactory results. The metalated species were characterized in situ by NMR spectroscopy and in two cases isolated as crystalline solids. Single-crystal XRD studies revealed the presence of salt-like structures with strongly interacting ions. Synthetic applications of K[(R2 N)2 P(BH3 )] were studied in reactions with a 1,2-dichlorodisilane and CS2 , which afforded either mono- or difunctional phosphine boranes with a rare combination of electronegative amino and electropositive functional disilanyl groups on phosphorus, or a phosphinodithioformate. Spectroscopic studies gave a first hint that removal of the borane fragment may be feasible.

| S-EPMC7756230 | biostudies-literature

Divergent transcriptional regulation of astrocyte reactivity across disorders [TR_ATAC_SCI]

Project description:Single-nuclei Assay for Transposase-Accessible Chromatin with sequencing (snATACseq) was applied to examine chromatin landscape changes and transcriptional regulator (TR) DNA motif accessibility in reactive astrocytes following traumatic spinal cord injury (SCI). Astrocyte nuclei were isolated from the spinal cord of wild type mice and mice with astrocyte-specific conditional gene deletion (cKO) of test-case TRs, SMARCA4 (Smarca4-astro-cKO) or STAT3 knockout (Stat3-astro-cKO). Comparison of differential chromatin accessibility revealed substantial remodeling during astrocyte reactivity, with more chromatin opening than closing. Marked alterations in access to SCI reactivity-associated TR motifs were also detected.

2022-05-26 | GSE199481 | GEO

Divergent transcriptional regulation of astrocyte reactivity across disorders [TR_ATAC_LPS]

Project description:Single-nuclei Assay for Transposase-Accessible Chromatin with sequencing (snATACseq) was applied to examine chromatin landscape changes and transcriptional regulator (TR) DNA motif accessibility in reactive astrocytes following neuroinflammatory insult by systemic administration of lipopolysaccharide (LPS). Astrocyte nuclei were isolated from the spinal cord of wild type mice and mice with astrocyte-specific conditional gene deletion (cKO) of test-case TRs, SMARCA4 (Smarca4-astro-cKO) or STAT3 knockout (Stat3-astro-cKO). Comparison of differential chromatin accessibility revealed substantial remodeling during astrocyte reactivity, with more chromatin opening than closing. Marked alterations in access to LPS reactivity-associated TR motifs were also detected.

2022-05-26 | GSE199480 | GEO

Divergent transcriptional regulation of astrocyte reactivity across disorders [RNA-seq]

Project description:RNA sequencing was applied to examine changes in gene expression in reactive astrocytes following traumatic spinal cord injury (SCI) or neuroinflammatory insult by systemic administration of lipopolysaccharide (LPS). Transgenic Ribotag technology was used to isolate astrocyte ribosome-associated mRNAs from the spinal cord of wild type mice and mice with astrocyte-specific conditional gene deletion (cKO) of test-case transcriptional regulators of reactivity, SMARCA4 (Smarca4-astro-cKO) or STAT3 knockout (Stat3-astro-cKO). Examination of differentially expressed gene (DEG) profiles by upstream transcriptional regulator enrichment analysis (TREA) was used identify transcriptional regulators of reactivity in each condition. Together, findings from this study show that transcriptional changes associated with astrocyte reactivity are exquisitely heterogeneous and are customized from vast numbers of potential DEGs via context-specific combinatorial TR interactions. These data have also been made accessible in a open-access, searchable database: http://tr.astrocytereactivity.com

2022-05-26 | GSE199149 | GEO

Divergent Reactivity of Rhodium(I) Carbenes Derived from Indole Annulations.

Project description:Rhodium(I) carbenes were generated from propargylic alcohol derivatives as the result of a dehydrative indole annulation. Depending on the choice of the electron-withdrawing group on the aniline nitrogen nucleophile, either a cyclopropanation product or dimerization product was obtained chemoselectively. Intramolecular hydroamidation occurred for the same type of propargylic alcohol derivatives when other transition-metal catalysts were employed.

| S-EPMC4612373 | biostudies-literature

An Isolable Bis(Silanone-Borane) Adduct.

Project description:The reaction of bis(silylenyl)-substituted ferrocene 1 with two molar equivalents of BPh3 yields the corresponding bis(silylene-borane) Lewis adduct 2. The latter is capable to activate CO2 to furnish the borane-stabilized bis(silanone) 3 through mono-oxygenation of the dative SiII ?B silicon centers under release of CO. Removal of BPh3 from 3 with PMe3 affords the corresponding 1,3,2,4-cyclodisiloxane and the Me3 P-BPh3 adduct. All isolated new compounds were characterized and their molecular structures were determined by single-crystal X-ray diffraction analyses.

| S-EPMC7187440 | biostudies-literature

Isolable Silicon-Based Polycations with Lewis Superacidity.

Project description:Molecular silicon polycations of the types R2 Si2+ and RSi3+ (R=H, organic groups) are elusive Lewis superacids and currently unknown in the condensed phase. Here, we report the synthesis of a series of isolable terpyridine-stabilized R2 Si2+ and RSi3+ complexes, [R2 Si(terpy)]2+ (R=Ph 12+ ; R2 =C12 H8 22+ , (CH2 )3 32+ ) and [RSi(terpy)]3+ (R=Ph 43+ , cyclohexyl 53+ , m-xylyl 63+ ), in form of their triflate salts. The stabilization of the latter is achieved through higher coordination and to the expense of reduced fluoride-ion affinities, but a significant level of Lewis superacidity is nonetheless retained as verified by theory and experiment. The complexes activate C(sp3 )-F bonds, as showcased by stoichiometric fluoride abstraction from 1-fluoroadamantane (AdF) and the catalytic hydrodefluorination of AdF. The formation of the crystalline adducts [2(F)]+ and [5(H)]2+ documents in particular the high reactivity towards fluoride and hydride donors.

| S-EPMC7756528 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data