Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Chemoselective Nozaki-Hiyama-Takai-Kishi and Grignard reaction: short synthesis of some carbahexopyranoses.

ABSTRACT: A common, divergent, efficient, stereoselective and short approach for the total syntheses of some carbahexopyranoses namely, MK7607, (-)-gabosine A, (-)-conduritol E, (-)-conduritol F, 6a-carba-β-d-fructopyranose and other carbasugars using chemoselective Grignard or Nozaki-Hiyama-Takai-Kishi (NHTK) reactions and RCM. Herein, the Grignard and NHTK reactions are able to differentiate the reactivity difference between lactol or lactolacetate and aldehyde of 2 & 6 under given conditions to give the desired skeleton chemoselectivity.

SUBMITTER: Vinaykumar A

PROVIDER: S-EPMC10375257 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Chemoselective Nozaki-Hiyama-Takai-Kishi and Grignard reaction: short synthesis of some carbahexopyranoses.

Vinaykumar Allam A Surender Banothu B Rao Batchu Venkateswara BV

RSC advances 20230728 33

A common, divergent, efficient, stereoselective and short approach for the total syntheses of some carbahexopyranoses namely, MK7607, (-)-gabosine A, (-)-conduritol E, (-)-conduritol F, 6a-carba-β-d-fructopyranose and other carbasugars using chemoselective Grignard or Nozaki-Hiyama-Takai-Kishi (NHTK) reactions and RCM. Herein, the Grignard and NHTK reactions are able to differentiate the reactivity difference between lactol or lactolacetate and aldehyde of 2 & 6 under given conditions to give th ...[more]

PMID: 37520087

Similar Datasets

Total synthesis of LL-Z1640-2 utilizing a late-stage intramolecular Nozaki-Hiyama-Kishi reaction.

Project description:A total synthesis of LL-Z1640-2 (2), a potent and selective kinase inhibitor, has been completed. The key step of the convergent synthesis utilized a late-stage intramolecular Nozaki-Hiyama-Kishi (NHK) reaction to close the macrocycle at the C6'-C7' bond.

| S-EPMC3079232 | biostudies-literature

Electrochemical Nozaki-Hiyama-Kishi Coupling: Scope, Applications, and Mechanism.

Project description:One of the most oft-employed methods for C-C bond formation involving the coupling of vinyl-halides with aldehydes catalyzed by Ni and Cr (Nozaki-Hiyama-Kishi, NHK) has been rendered more practical using an electroreductive manifold. Although early studies pointed to the feasibility of such a process, those precedents were never applied by others due to cumbersome setups and limited scope. Here we show that a carefully optimized electroreductive procedure can enable a more sustainable approach to NHK, even in an asymmetric fashion on highly complex medicinally relevant systems. The e-NHK can even enable non-canonical substrate classes, such as redox-active esters, to participate with low loadings of Cr when conventional chemical techniques fail. A combination of detailed kinetics, cyclic voltammetry, and in situ UV-vis spectroelectrochemistry of these processes illuminates the subtle features of this mechanistically intricate process.

| S-EPMC8720499 | biostudies-literature

Synthesis of the Core Framework of the Cornexistins by Intramolecular Nozaki-Hiyama-Kishi Coupling.

Project description:A new and direct approach to the construction of the core framework of the herbicidal natural products cornexistin and hydroxycornexistin has been developed. Formation of the nine-membered carbocycle found in the natural products has been accomplished by an intramolecular Nozaki-Hiyama-Kishi reaction between a vinylic iodide and an aldehyde. Good yields of carbocyclic products were obtained from the reaction, but diastereomeric mixtures of allylic alcohols were produced. The cyclisation reaction was successful irrespective of the relative configuration of the stereogenic centres in the cyclisation precursor.

| S-EPMC6680490 | biostudies-literature

Electrocatalytic Asymmetric Nozaki-Hiyama-Kishi Decarboxylative Coupling: Scope, Applications, and Mechanism.

Project description:The first general enantioselective alkyl-Nozaki-Hiyama-Kishi (NHK) coupling reactions are disclosed herein by employing a Cr-electrocatalytic decarboxylative approach. Using easily accessible aliphatic carboxylic acids (via redox-active esters) as alkyl nucleophile synthons, in combination with aldehydes and enabling additives, chiral secondary alcohols are produced in a good yield with high enantioselectivity under mild reductive electrolysis. This reaction, which cannot be mimicked using stoichiometric metal or organic reductants, tolerates a broad range of functional groups and is successfully applied to dramatically simplify the synthesis of multiple medicinally relevant structures and natural products. Mechanistic studies revealed that this asymmetric alkyl e-NHK reaction was enabled by using catalytic tetrakis(dimethylamino)ethylene, which acts as a key reductive mediator to mediate the electroreduction of the CrIII/chiral ligand complex.

| S-EPMC11456316 | biostudies-literature

Enantioselective Nozaki-Hiyama-Kishi allylation-lactonization for the syntheses of 3-substituted phthalides.

Project description:We report the synthesis of bipyridyl ligands and these ligands were applied in the chromium-catalyzed enantioselective Nozaki-Hiyama-Kishi allylation of substituted (2-ethoxycarbonyl)benzaldehydes and subsequently lactonized to synthesize phthalides with an optimal enantioselectivity of 99%. This approach was applied to synthesize (S)-cytosporone E at a 71% yield in three steps.

| S-EPMC9091628 | biostudies-literature

Catalytic enantioselective Grignard Nozaki-Hiyama methallylation from the alcohol oxidation level: chloride compensates for π-complex instability.

Project description:Methallyl chloride serves as an efficient allyl donor in highly enantioselective Grignard Nozaki-Hiyama methallylations from the alcohol or aldehyde oxidation level via iridium catalyzed transfer hydrogenation. Under identical conditions, methallyl acetate does not react efficiently. Double methallylation of 1,3-propanediol provides the C(2)-symmetric adduct as a single enantiomer, as determined by HPLC analysis.

| S-EPMC3225001 | biostudies-literature

Rhodium-Catalyzed Aldehyde Arylation via Formate-Mediated Transfer Hydrogenation: Beyond Metallic Reductants in Grignard/Nozaki-Hiyami-Kishi-Type Addition.

Project description:The first intermolecular carbonyl arylations via transfer hydrogenative reductive coupling are described. Using rhodium catalysts modified by tBu2PMe, sodium formate-mediated reductive coupling of aryl iodides with aldehydes occurs in a chemoselective fashion in the presence of protic functional groups and lower halides. This work expands the emerging paradigm of transfer hydrogenative coupling as an alternative to pre-formed carbanions or metallic reductants in C═X addition.

| S-EPMC6376962 | biostudies-literature

A sequential esterification-ring closing metathesis-Nozaki-Hiyama-Kishi strategy for constructing a natural product-like library of tetrahydrofuran-containing macrolides.

Project description:Polyketide-like macrolides (pMLs) represent a privileged class of compounds with a high incidence of bioactivity, however their structural complexity challenges their synthesis and more general study. Here we report the synthesis of a library of tetrahydrofuran-containing pMLs underpinned by a robust and convergent build/couple/pair/couple synthetic approach. The library comprises 170 pMLs originating from 17 building blocks, 10 of which were synthesized using a proline-catalyzed α-chlorination aldol reaction. Northern and southern hemisphere building blocks were coupled using either an oxidation/Horner-Wadsworth-Emmons sequence or a saponification/Steglich esterification strategy. Coupled fragments were cyclized via ring closing metathesis to yield macrocycles 14-16 atoms in size, which we diversified using 3 eastern side chain vinyl iodides through a Nozaki-Hiyama-Kishi reaction.

| S-EPMC11884414 | biostudies-literature

An efficient Nozaki-Hiyama allenylation promoted by the acid derived MIL-101 MOF.

Project description:A concise synthesis of the sulfonic acid-containing MIL-101 MOF catalyst was reported using commercially available materials. A series of characterization of as-synthesized MIL-101-SO3H including SEM, XRD, FTIR, BET and TGA was also demonstrated. Using MIL-101-SO3H as a catalyst, an efficient Nozaki-Hiyama allenylation reaction was achieved to generate various polyfunctionalized α-allenic alcohols in high yield and good selectivity. Taking advantage of the high acidity of the MIL-101-SO3H MOF structure, such transformations were also achieved under mild reaction conditions and short reaction times. Based on our observed evidence during this study, a mechanism was proposed involving a substrate activation/γ-nucleophilic addition reaction sequence. In addition, the MIL-101-SO3H catalyst can be recycled ten times during the Nozaki-Hiyama allenylation reaction without compromising the yield and selectivity.

| S-EPMC9061183 | biostudies-literature

Total Synthesis of Penicyclone A Using a Double Grignard Reaction.

Project description:We describe the first total synthesis of penicyclone A, a novel deep-sea fungus-derived polyketide, and a reevaluation of its antimicrobial activity. The synthesis of this unique spirolactone was achieved in 10 steps starting from a known d-ribose derivative. The key steps include a double Grignard reaction for the diastereoselective construction of the chiral tertiary alcohol intermediate, tandem oxidation/cyclization, and photooxygenation, followed by an oxidative rearrangement to introduce the enone functionality.

| S-EPMC9724088 | 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