Browse
Submit Data
Databases
API
Help

Dataset Information

10 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Diastereoselective synthesis of pentasubstituted gamma-butyrolactones from silyl glyoxylates and ketones through a double Reformatsky reaction.

ABSTRACT: Three contiguous stereocenters can be established with remarkable diastereoselectivity in a double Reformatsky sequence. Densely functionalized gamma-butyrolactones were assembled rapidly by this approach, in which a ketone is used as the terminal electrophile (see scheme). Secondary transformations of the lactone products enhance their synthetic utility. R(1) = Me, H; R(2) = alkyl, aryl, CF(3); Bn = benzyl, TBS = tert-butyldimethylsilyl.

SUBMITTER: Greszler SN

PROVIDER: S-EPMC2801152 | biostudies-literature | 2009

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Diastereoselective synthesis of pentasubstituted gamma-butyrolactones from silyl glyoxylates and ketones through a double Reformatsky reaction.

Greszler Stephen N SN Johnson Jeffrey S JS

Angewandte Chemie (International ed. in English) 20090101 20

Three contiguous stereocenters can be established with remarkable diastereoselectivity in a double Reformatsky sequence. Densely functionalized gamma-butyrolactones were assembled rapidly by this approach, in which a ketone is used as the terminal electrophile (see scheme). Secondary transformations of the lactone products enhance their synthetic utility. R(1) = Me, H; R(2) = alkyl, aryl, CF(3); Bn = benzyl, TBS = tert-butyldimethylsilyl. ...[more]

PMID: 19373816

Similar Datasets

Formal synthesis of leustroducsin B via Reformatsky/Claisen condensation of silyl glyoxylates.

Project description:A formal synthesis of leustroducsin B has been completed. The synthesis relies upon a recently developed Reformatsky/Claisen condensation of silyl glyoxylates and enantioenriched ?-lactones that establishes two of the molecule's three core stereocenters and permits further elaboration to an intermediate in Imanishi's synthesis via reliable chemistry (Prasad reduction, asymmetric pentenylation, Mitsunobu inversion).

| S-EPMC3115596 | biostudies-literature

Remote stereoinduction in the acylation of fully substituted enolates: tandem Reformatsky/quaternary Claisen condensations of silyl glyoxylates and ?-lactones.

Project description:Reformatsky reagents react sequentially with silyl glyoxylates and ?-lactones to give highly functionalized Claisen condensation products. A heretofore undocumented instance of stereochemical 1,4-induction results in efficient transmission of ?-lactone stereochemistry to the emerging fully substituted stereocenter. Second-stage transformations reveal that the five heteroatom-containing functionalities embedded within the products are entirely chemo-differentiated, a circumstance that permits rapid assembly of the leustroducsin B core substructure.

| S-EPMC3056164 | biostudies-literature

Three-component coupling reactions of silyl glyoxylates, vinyl Grignard reagent, and nitroalkenes: an efficient, highly diastereoselective approach to nitrocyclopentanols.

Project description: Not available

| S-EPMC3003293 | biostudies-literature

Catalytic redox-initiated glycolate aldol additions of silyl glyoxylates.

Project description:Lanthanide triisopropoxides catalyze a rapid, tandem MPV reduction/Brook rearrangement/aldol sequence between silyl glyoxylates and aldehydes that achieves catalytic turnover through alkoxide transfer from a strain-release Lewis acidic silacycle.

| S-EPMC2651742 | biostudies-literature

A highly diastereoselective "super silyl" governed aldol reaction: synthesis of ?,?-dioxyaldehydes and 1,2,3-triols.

Project description:A highly diastereoselective approach for the synthesis of protected ?,?-dioxyaldehydes derived from (Z)-tris(trimethylsilyl)silyl "super silyl" enol ethers is described. A general and highly syn-stereoselective aldol reaction directed by the "super silyl" group catalyzed by triflimide (HNTf2) is developed providing ?,?-dioxyaldehydes and 1,2,3-triol fragments which can be a useful platform for the elaboration of natural and unnatural sugar derivatives.

| S-EPMC5952264 | biostudies-literature

Diastereoselective Prins-type reaction of cycloalkenylcyclopropanol silyl ethers and alpha,beta-unsaturated aldehyde acetals.

Project description:Electrophilic addition of 1-(1-cyclohexenyl)-1-cyclopropanol trimethylsilyl ether to alpha,beta-unsaturated aldehyde acetals under Lewis acidic conditions proceeds with good to excellent diastereoselectivity to afford spirocyclobutanones containing three contiguous stereocenters. A convenient entry to enantioselective syntheses is available by use of a nonracemic C2-symmetric acetal. Elaboration of the resulting adducts provides ready access to medium-sized carbocycles.

| S-EPMC2597285 | biostudies-literature

Three-component glycolate Michael reactions of enolates, silyl glyoxylates, and ?,?-enones.

Project description:Silyl glyoxylates react with enolates and enones to afford either glycolate aldol or Michael adducts. Product identity is controlled by the countercation associated with the enolate. Reformatsky nucleophiles in the presence of additional Zn(OTf)(2) result in aldol coupling (A), while lithium enolates provide the Michael coupling (B). Deprotonation of the aldol product A with LDA induces equilibration to form the minor diastereomer of Michael product B. This observation suggests that formation of the major diastereomer of Michael product B does not occur via an aldol/retro-aldol/Michael sequence.

| S-EPMC3321131 | biostudies-literature

A Ball-Milling-Enabled Reformatsky Reaction.

Project description:An operationally simple one-jar one-step mechanochemical Reformatsky reaction using in situ generated organozinc intermediates under neat grinding conditions has been developed. Notable features of this reaction protocol are that it requires no solvent, no inert gases, and no pre-activation of the bulk zinc source. The developed process is demonstrated to have good substrate scope (39-82?% yield) and is effective irrespective of the initial morphology of the zinc source.

| S-EPMC6619031 | biostudies-literature

N-triflylthiophosphoramide catalyzed enantioselective Mukaiyama aldol reaction of aldehydes with silyl enol ethers of ketones.

Project description:The first Brønsted acid catalyzed asymmetric Mukaiyama aldol reaction of aldehydes using silyl enol ethers of ketones as nucleophiles has been reported. A variety of aldehydes and silyl enol ethers of ketones afforded the aldol products in excellent yields and good to excellent enantioselectivities. Mechanistic studies revealed that the actual catalyst may be changed from the silylated Brønsted acid to the Brønsted acid itself depending on the reaction temperature.

| S-EPMC2887700 | biostudies-literature

Towards the Total Synthesis of Pl-3: Preparation of the Eastern Fragment through a Diastereoselective SmI<sub>2</sub>-Mediated Reformatsky Reaction.

Project description:The jatrophane diterpene Pl-3, isolated in 2003 from Euphorbia platyphyllos, is a structurally complex natural product with highly promising biological properties that include pronounced antiproliferative activity and the inhibition of the efflux-pump activity of multidrug resistance p-glycoprotein. Herein, the synthesis of the eastern fragment of Pl-3 is outlined. The target compound is synthesized in nine synthetic operations in good overall yield, starting from readily available d-ribose. The key step in the preparation of the eastern part of Pl-3 is a diastereoselective SmI2-mediated Reformatsky reaction. The proposed route is highly flexible and could also be applied to the synthesis of structurally related jatrophane diterpenes.

| S-EPMC3654569 | 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