Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Regiospecific decarboxylative allylation of nitriles.

ABSTRACT: Palladium-catalyzed decarboxylative alpha-allylation of nitriles readily occurs with use of Pd(2)(dba)(3) and rac-BINAP. This catalyst mixture also allows the highly regiospecific alpha-allylation of nitriles in the presence of much more acidic alpha-protons. Thus, the reported method provides access to compounds that are not readily available via base-mediated allylation chemistries. Lastly, mechanistic investigations indicate that there is a competition between C- and N-allylation of an intermediate nitrile-stabilized anion and that N-allylation is followed by a rapid [3,3]-sigmatropic rearrangement.

SUBMITTER: Recio A

PROVIDER: S-EPMC2794903 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Regiospecific decarboxylative allylation of nitriles.

Recio Antonio A Tunge Jon A JA

Organic letters 20091201 24

Palladium-catalyzed decarboxylative alpha-allylation of nitriles readily occurs with use of Pd(2)(dba)(3) and rac-BINAP. This catalyst mixture also allows the highly regiospecific alpha-allylation of nitriles in the presence of much more acidic alpha-protons. Thus, the reported method provides access to compounds that are not readily available via base-mediated allylation chemistries. Lastly, mechanistic investigations indicate that there is a competition between C- and N-allylation of an interm ...[more]

PMID: 19921827

Similar Datasets

Rapid decarboxylative allylation of nitroalkanes.

Project description:Allyl nitroacetates undergo decarboxylative allylation to provide tertiary nitroalkanes in high yield. Moreover, the transformations are complete within several minutes under ambient conditions. High yields result because O-allylation of the intermediate nitronates, which is typically problematic, is reversible under conditions of the decarboxylative allylation process. Lastly, the preparation of substrate allyl nitroacetates by tandem Knoevenagel/Diels-Alder sequences allows the facile synthesis of relatively complex substrates that undergo diastereoselective decarboxylative allylation.

| S-EPMC2821453 | biostudies-literature

Mild decarboxylative allylation of coumarins.

Project description:Allyl esters of 3-carboxylcoumarins undergo facile decarboxylative coupling at just 25-50 degrees C. This represents the first extension of decarboxylative C-C bond-forming reactions to the coupling of aromatics with sp(3)-hybridized electrophiles. Finally, the same concept can be applied to the sp(2)-sp(3) couplings of pyrones and flavones. Thus, a variety of biologically important heteroaromatics can be readily functionalized without the need for strong bases or stoichiometric organometallics that are typically required for more standard cross-coupling reactions.

| S-EPMC2878741 | biostudies-literature

Stereospecific decarboxylative allylation of sulfones.

Project description:Allyl sulfonylacetic esters undergo highly stereospecific, palladium-catalyzed decarboxylative allylation. The reaction allows the stereospecific formation of tertiary homoallylic sulfones in high yield. In contrast to related reactions that proceed at -100 degrees C and require highly basic preformed organometallics, the decarboxylative coupling described herein occurs under mild nonbasic conditions and requires no stoichiometric additives. Allylation of the intermediate alpha-sulfonyl anion is more rapid than racemization, leading to a highly enantiospecific process. Density functional theory calculations indicate that the barrier for racemization is 9.9 kcal/mol, so the barrier for allylation must be <9.9 kcal/mol.

| S-EPMC2935626 | biostudies-literature

Mechanistic origin of the stereodivergence in decarboxylative allylation.

Project description:A stereochemical test has been used to probe the mechanism of decarboxylative allylation. This probe suggests that the mechanism of DcA reactions can change based on the substitution pattern at the alpha-carbon of the nucleophile; however, reaction via stabilized malonate nucleophiles is the lower energy pathway. Lastly, this mechanistic proposal has predictive power and can be used to explain chemoselectivities in decarboxylative reactions that were previously confounding.

| S-EPMC2913676 | biostudies-literature

Decarboxylative allylation using sulfones as surrogates of alkanes.

Project description:Alpha-sulfonyl functional groups are traceless activating groups that facilitate catalytic decarboxylative allylations in high yield yet can be cleaved to allow the synthesis of simple allylated alkanes. Substrate studies suggest that decarboxylation to form an alpha-sulfonyl anion is rate-limiting. Furthermore, the anion is formed regiospecifically under formally neutral conditions.

| S-EPMC2754783 | biostudies-literature

Decarboxylative allylation of amino alkanoic acids and esters via dual catalysis.

Project description:A combination of photoredox and palladium catalysis has been employed to facilitate the room temperature decarboxylative allylation of recalcitrant ?-amino and phenylacetic allyl esters. This operationally simple process produces CO2 as the only byproduct and provides direct access to allylated alkanes. After photochemical oxidation, the carboxylate undergoes radical decarboxylation to site-specifically generate radical intermediates which undergo allylation. A radical dual catalysis mechanism is proposed. Free phenylacetic acids were also allylated utilizing similar reactions conditions.

| S-EPMC4183636 | biostudies-literature

Palladium-catalyzed decarboxylative allylation and benzylation of N-alloc and N-Cbz indoles.

Project description:A set of general methods for the palladium-catalyzed decarboxylative C3-allylation and C3-benzylation of indoles, starting from the corresponding N-alloc and N-Cbz indoles, respectively, is reported. This chemistry provides ready access to a wide range of functionalized indolenines in good to excellent yields. A tandem process, wherein the palladium catalyzed allylation chemistry is coupled with a Mizoroki-Heck reaction, offers a simple route to cinnamylated products.

| S-EPMC3980966 | biostudies-literature

Ligand-controlled regiodivergent palladium-catalyzed decarboxylative allylation reaction to access α,α-difluoroketones.

Project description:α,α-Difluoroketones possess unique physicochemical properties that are useful for developing therapeutics and probes for chemical biology. To access the α-allyl-α,α-difluoroketone substructure, complementary palladium-catalyzed decarboxylative allylation reactions were developed to provide linear and branched α-allyl-α,α-difluoroketones. For these orthogonal processes, the fluorination pattern of the substrate enabled the ligands to dictate the regioselectivity of the transformations.

| S-EPMC4373536 | biostudies-literature

Decarboxylative alkenylation.

Project description:Olefin chemistry, through pericyclic reactions, polymerizations, oxidations, or reductions, has an essential role in the manipulation of organic matter. Despite its importance, olefin synthesis still relies largely on chemistry introduced more than three decades ago, with metathesis being the most recent addition. Here we describe a simple method of accessing olefins with any substitution pattern or geometry from one of the most ubiquitous and variegated building blocks of chemistry: alkyl carboxylic acids. The activating principles used in amide-bond synthesis can therefore be used, with nickel- or iron-based catalysis, to extract carbon dioxide from a carboxylic acid and economically replace it with an organozinc-derived olefin on a molar scale. We prepare more than 60 olefins across a range of substrate classes, and the ability to simplify retrosynthetic analysis is exemplified with the preparation of 16 different natural products across 10 different families.

| S-EPMC5478194 | biostudies-literature

Decarboxylative Alkynylation.

Project description:The development of a new decarboxylative cross-coupling method that affords terminal and substituted alkynes from various carboxylic acids is described using both nickel- and iron-based catalysts. The use of N-hydroxytetrachlorophthalimide (TCNHPI) esters is crucial to the success of the transformation, and the reaction is amenable to in?situ carboxylic acid activation. Additionally, an inexpensive, commercially available alkyne source is employed in this formal homologation process that serves as a surrogate for other well-established alkyne syntheses. The reaction is operationally simple and broad in scope while providing succinct and scalable avenues to previously reported synthetic intermediates.

| S-EPMC5792189 | 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