Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Enantioselective Synthesis of Spiroindenes by Enol-Directed Rhodium(III)-Catalyzed C-H Functionalization and Spiroannulation.

ABSTRACT: Chiral cyclopentadienyl rhodium complexes promote highly enantioselective enol-directed C(sp(2))-H functionalization and oxidative annulation with alkynes to give spiroindenes containing all-carbon quaternary stereocenters. High selectivity between two possible directing groups, as well as control of the direction of rotation in the isomerization of an O-bound rhodium enolate into the C-bound isomer, appear to be critical for high enantiomeric excesses.

SUBMITTER: Reddy Chidipudi S

PROVIDER: S-EPMC4648053 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Enantioselective Synthesis of Spiroindenes by Enol-Directed Rhodium(III)-Catalyzed C-H Functionalization and Spiroannulation.

Reddy Chidipudi Suresh S Burns David J DJ Khan Imtiaz I Lam Hon Wai HW

Angewandte Chemie (International ed. in English) 20150925 47

Chiral cyclopentadienyl rhodium complexes promote highly enantioselective enol-directed C(sp(2))-H functionalization and oxidative annulation with alkynes to give spiroindenes containing all-carbon quaternary stereocenters. High selectivity between two possible directing groups, as well as control of the direction of rotation in the isomerization of an O-bound rhodium enolate into the C-bound isomer, appear to be critical for high enantiomeric excesses. ...[more]

PMID: 26404643

Similar Datasets

Rhodium-catalyzed enantioselective vinylogous addition of enol ethers to vinyldiazoacetates.

Project description:A highly asymmetric vinylogous addition of acyclic silyl enol ethers to siloxyvinyldiazoacetate is described. The reaction features a diastereoselective 1,4-siloxy group migration event. Products are obtained in up to 97% ee. When more sterically crowded silyl enol ethers are employed, an enantioselective formal [3+2] cycloaddition becomes the dominant reaction pathway. Control experiments reveal the (Z)-olefin geometry to be critical for high levels of enantiocontrol.

| S-EPMC3549400 | biostudies-literature

Rhodium(II)-catalyzed enantioselective C-H functionalization of indoles.

Project description:A catalytic, enantioselective method for the C-H functionalization of indoles by diazo compounds has been achieved. With catalytic amounts of Rh(2)(S-NTTL)(4), the putative Rh-carbene intermediates from α-alkyl-α-diazoesters react with indoles at C(3) to provide α-alkyl-α-indolylacetates in high yield and enantioselectivity. From DFT calculations, a mechanism is proposed that involves a Rh-ylide intermediate with oxocarbenium character.

| S-EPMC3144986 | biostudies-literature

Rhodium(III)-catalyzed indazole synthesis by C-H bond functionalization and cyclative capture.

Project description:An efficient, one-step, and highly functional group-compatible synthesis of substituted N-aryl-2H-indazoles is reported via the rhodium(III)-catalyzed C-H bond addition of azobenzenes to aldehydes. The regioselective coupling of unsymmetrical azobenzenes was further demonstrated and led to the development of a new removable aryl group that allows for the preparation of indazoles without N-substitution. The 2-aryl-2H-indazole products also represent a new class of readily prepared fluorophores for which initial spectroscopic characterization has been performed.

| S-EPMC3656829 | biostudies-literature

Rhodium(III)-catalyzed alkenyl C-H bond functionalization: convergent synthesis of furans and pyrroles.

Project description:Ring in the new: a new annulation for the efficient synthesis of substituted furans and pyrroles is reported. The Rh(III) -catalyzed reaction of O-methyl α,β-unsaturated oximes with aldehydes and N-tosyl imines affords secondary alcohol and amine intermediates, respectively. Cyclization and aromatization occurs under the reaction conditions to provide access to biologically relevant furans and pyrroles in good yields. Cp*=C(5)Me(5), DCE=1,2-dichloroethane, THF=tetrahydrofuran.

| S-EPMC3770945 | biostudies-literature

Enantioselective Rhodium(III)-Catalyzed Markovnikov Hydroboration of Unactivated Terminal Alkenes.

Project description:We report the first enantioselective Rh-catalyzed Markovnikov hydroboration of unactivated terminal alkenes. Using a novel sp2-sp3 hybridized diboron reagent and water as a proton source, a broad range of alkenes undergo hydroboration to provide secondary boronic esters with high regio- and enantiocontrol.

| S-EPMC5515510 | biostudies-literature

Thioketone-directed rhodium(I) catalyzed enantioselective C-H bond arylation of ferrocenes.

Project description:Planar chiral ferrocenes have received great attention in both academia and industry. Although remarkable progresses have been made over the past decade, the development of efficient and straightforward methods for the synthesis of enantiopure planar chiral ferrocenes remains highly challenging. Herein, we report a rhodium(I)/phosphonite catalyzed thioketone-directed enantioselective C-H bond arylation of ferrocenes. Readily available aryl iodides are used as the coupling partners in this transformation, leading to a series of planar chiral ferrocenes in good yields and excellent enantioselectivities (up to 86% yield, 99% ee). Of particular note, heteroaryl coupled ferrocenes, which are difficult to access with previous approaches, can be obtained in satisfactory results.

| S-EPMC6744407 | biostudies-other

Rhodium(III)-catalyzed arylation of Boc-imines via C-H bond functionalization.

Project description:The first rhodium-catalyzed arylation of imines proceeding via C-H bond functionalization is reported. Use of a non-coordinating halide abstractor is important to obtain reactivity. Aryl-branched N-Boc-amines are formed, and a wide range of functionality is compatible with the reaction.

| S-EPMC3045530 | biostudies-literature

Synthesis of [5,6]-Bicyclic Heterocycles with a Ring-Junction Nitrogen Atom: Rhodium(III)-Catalyzed C-H Functionalization of Alkenyl Azoles.

Project description:The first syntheses of privileged [5,6]-bicyclic heterocycles, with ring-junction nitrogen atoms, by transition metal catalyzed C-H functionalization of C-alkenyl azoles is disclosed. Several reactions are applied to alkenyl imidazoles, pyrazoles, and triazoles to provide products with nitrogen incorporated at different sites. Alkyne and diazoketone coupling partners give azolopyridines with various substitution patterns. In addition, 1,4,2-dioxazolone coupling partners yield azolopyrimidines. Furthermore, the mechanisms for the reactions are discussed and the utility of the developed approach is demonstrated by iterative application of C-H functionalization for the rapid synthesis of a patented drug candidate.

| S-EPMC5564303 | biostudies-literature

Selective Synthesis of <i>Z</i>-Silyl Enol Ethers via Ni-Catalyzed Remote Functionalization of Ketones.

Project description:We report a remote functionalization strategy, which allows the Z-selective synthesis of silyl enol ethers of (hetero)aromatic and aliphatic ketones via Ni-catalyzed chain walking from a distant olefin site. The positional selectivity is controlled by the directionality of the chain walk and is independent of thermodynamic preferences of the resulting silyl enol ether. Our mechanistic data indicate that a Ni(I) dimer is formed under these conditions, which serves as a catalyst resting state and, upon reaction with an alkyl bromide, is converted to [Ni(II)-H] as an active chain-walking/functionalization catalyst, ultimately generating a stabilized η3-bound Ni(II) enolate as the key selectivity-controlling intermediate.

| S-EPMC8193638 | biostudies-literature

Traceless Rhodium-Catalyzed Hydroacylation Using Alkyl Aldehydes: The Enantioselective Synthesis of β-Aryl Ketones.

Project description:A one-pot three-step sequence involving Rh-catalyzed alkene hydroacylation, sulfide elimination and Rh-catalyzed aryl boronic acid conjugate addition gave products of traceless chelation-controlled hydroacylation employing alkyl aldehydes. The stereodefined β-aryl ketones were obtained in good yields with excellent control of enantioselectivity. Good variation of all three reaction components is possible.

| S-EPMC5396316 | 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