Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Titanocene(III)-catalyzed formation of indolines and azaindolines.

ABSTRACT: Reductive cyclization of epoxides tethered to substituted anilines and aminopyridines in the presence of 3 mol % of titanocene dichloride and stoichiometric manganese metal promotes a radical annulation to form 3,3-disubstituted indolines and azaindolines.

SUBMITTER: Wipf P

PROVIDER: S-EPMC5467310 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Titanocene(III)-catalyzed formation of indolines and azaindolines.

Wipf Peter P Maciejewski John P JP

Organic letters 20080910 19

Reductive cyclization of epoxides tethered to substituted anilines and aminopyridines in the presence of 3 mol % of titanocene dichloride and stoichiometric manganese metal promotes a radical annulation to form 3,3-disubstituted indolines and azaindolines. ...[more]

PMID: 18781767

Similar Datasets

Titanocene(III)-Catalyzed Precision Deuteration of Epoxides.

Project description:We describe a titanocene(III)-catalyzed deuterosilylation of epoxides that provides β-deuterated anti-Markovnikov alcohols with excellent D-incorporation, in high yield, and often excellent diastereoselectivity after desilylation. The key to the success of the reaction is a novel activation method of Cp2 TiCl2 and (tBuC5 H4 )2 TiCl2 with BnMgBr and PhSiD3 to provide [(RC5 H4 )2 Ti(III)D] without isotope scrambling. It was developed after discovering an off-cycle scrambling with the previously described method. Our precision deuteration can be applied to the synthesis of drug precursors and highlights the power of combining radical chemistry with organometallic catalysis.

| S-EPMC9305931 | biostudies-literature

Exploring Short and Efficient Synthetic Routes Using Titanocene(III)-Catalyzed Reactions: Total Synthesis of Natural Meroterpenes with Trisubstituted Unsaturations.

Project description:The stereo- and regioselective total syntheses of OMe derivatives of the scarce bioactive meroterpenoids makassaric acid (1) and fascioquinol B (2) have been accomplished. The synthetic sequences are based on the following three efficient and selective catalytic reactions: Cu-catalyzed addition of Grignard compounds to an epoxide; a regioselective Barbier-type reaction, catalyzed by Cp2TiCl; and regio- and stereoselective bioinspired cyclization, also catalyzed by Cp2TiCl. These three key processes allow us to obtain the main skeletons of 1 and 2 in a few steps. The valuable synthetic proposal shown in this work provides fast access to scarce, structurally complex meroterpenes with promising biological activities, which are a sustainable source for later studies and applications in medicine.

| S-EPMC9031794 | biostudies-literature

Rhodium-Catalyzed Enantioselective Hydroamination of Alkynes with Indolines.

Project description:The hydroamination of internal alkynes via tandem rhodium catalysis gives branched N-allylic indolines with high regio- and enantioselectivity. An acid switch provides access to the linear isomer in preference to the branched isomer by an isomerization mechanism. Mechanistic studies suggest formation of an allene intermediate, which undergoes hydroamination to generate allylic amines instead of the enamine or imine products typically observed in alkyne hydroaminations.

| S-EPMC4870006 | biostudies-literature

Rhodium-Catalyzed Hydrofunctionalization: Enantioselective Coupling of Indolines and 1,3-Dienes.

Project description:We communicate a strategy for the hydrofunctionalization of 1,3-dienes via Rh-hydride catalysis. Conjugated dienes are coupled to nucleophiles to demonstrate the feasibility of novel C-C, C-O, C-S, and C-N bond forming processes. In the presence of a chiral JoSPOphos ligand, hydroamination generates chiral allylic amines with high regio- and enantioselectivity. Tuning both the pKa and steric properties of an acid-additive is critical for enantiocontrol.

| S-EPMC6857534 | biostudies-literature

Highly diastereo- and enantioselective CuH-catalyzed synthesis of 2,3-disubstituted indolines.

Project description:A diastereo- and enantioselective CuH-catalyzed method for the preparation of highly functionalized indolines is reported. The mild reaction conditions and high degree of functional group compatibility as demonstrated with substrates bearing heterocycles, olefins, and substituted aromatic groups, renders this technique highly valuable for the synthesis of a variety of cis-2,3-disubstituted indolines in high yield and enantioeselectivity.

| S-EPMC4440622 | biostudies-literature

Synthesis of indolines via a domino Cu-catalyzed amidation/cyclization reaction.

Project description:A highly efficient one-pot procedure for the synthesis of indolines and their homologues based on a domino Cu-catalyzed amidation/nucleophilic substitution reaction has been developed. Substituted 2-iodophenethyl mesylates and related compounds afforded the corresponding products in excellent yields. No erosion of optical purity was observed when transforming enantiomerically pure mesylates under the reaction conditions.

| S-EPMC2489202 | biostudies-literature

Titanocene Selenide Sulfides Revisited: Formation, Stabilities, and NMR Spectroscopic Properties.

Project description:[TiCp₂S₅] (phase A), [TiCp₂Se₅] (phase F), and five solid solutions of mixed titanocene selenide sulfides [TiCp₂SexS₅-x] (Cp = C₅H₅-) with the initial Se:S ranging from 1:4 to 4:1 (phases B⁻E) were prepared by reduction of elemental sulfur or selenium or their mixtures by lithium triethylhydridoborate in thf followed by the treatment with titanocene dichloride [TiCp₂Cl₂]. Their 77Se and 13C NMR spectra were recorded from the CS₂ solution. The definite assignment of the 77Se NMR spectra was based on the PBE0/def2-TZVPP calculations of the 77Se chemical shifts and is supported by 13C NMR spectra of the samples. The following complexes in varying ratios were identified in the CS₂ solutions of the phases B⁻E: [TiCp₂Se₅] (5₁), [TiCp₂Se₄S] (4₁), [TiCp₂Se₃S₂] (3₁), [TiCp₂SSe₃S] (3₆), [TiCp₂SSe₂S₂] (2₅), [TiCp₂SSeS₃] (1₂), and [TiCp₂S₅] (0₁). The disorder scheme in the chalcogen atom positions of the phases B⁻E observed upon crystal structure determinations is consistent with the spectral assignment. The enthalpies of formation calculated for all twenty [TiCp₂SexS5-x] (x = 0⁻5) at DLPNO-CCSD(T)/CBS level including corrections for core-valence correlation and scalar relativistic, as well as spin-orbit coupling contributions indicated that within a given chemical composition, the isomers of most favourable enthalpy of formation were those, which were observed by 77Se and 13C NMR spectroscopy.

| S-EPMC6358803 | biostudies-literature

Epoc group: transformable protecting group with gold(iii)-catalyzed fluorene formation.

Project description:This study presents the novel concept of a transformable protecting group, which changes its properties through structural transformation. Based on this concept, we developed a 2-(2-ethynylphenyl)-2-(5-methylfuran-2-yl)-ethoxycarbonyl (Epoc) group. The Epoc group was transformed into an Fmoc-like structure with gold(iii)-catalyzed fluorene formation and was removable under Fmoc-like mild basic conditions post-transformation even though it was originally stable under strongly basic conditions. As an application for organic synthesis, the Epoc group provides the novel orthogonality of gold(iii)-labile protecting groups in solid-phase peptide synthesis. In addition, the high turnover number of fluorene formation in aqueous media is suggestive of the applicability of the Epoc group to biological systems.

| S-EPMC8372321 | biostudies-literature

Copper-Catalyzed Alkene Diamination: Synthesis of Chiral 2-Aminomethyl Indolines and Pyrrolidines.

Project description:Chiral vicinal diamines, including 2-aminomethyl indolines and pyrrolidines, are useful as ligands for catalytic asymmetric reactions and are also found as important components of bioactive compounds. Herein is reported the first copper-catalyzed alkene diamination that occurs with high enantioselectivity. The substrate range is the broadest yet reported for this kind of intra-/intermolecular reaction sequence both with respect to ?-alkenyl sulfonamide substrate and external amine nucleophile. The resulting products expand the availability of substituted 2-aminomethyl indolines and pyrrolidines, privileged compounds in asymmetric catalysis and medicinal chemistry. A unique solution to a challenging oxidation problem related to copper catalyst turnover is also presented.

| S-EPMC4051238 | biostudies-literature

Formal aromaticity transfer for palladium-catalyzed coupling between phenols and pyrrolidines/indolines.

Project description:We herein describe a palladium-catalyzed formal aromaticity transfer coupling reaction between phenols and pyrrolidines or indolines to generate the corresponding N-cyclohexyl pyrroles or indoles. In this transformation, the aromaticity of phenols is formally passed on to the pyrrolidine or indoline units. Substituted phenols thus can serve as latent cyclohexyl equivalents for the fast construction of various N-cyclohexyl pyrroles and indoles.

| S-EPMC5642148 | 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