Browse
Submit Data
Databases
API
Help

Dataset Information

33 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Facile formation of ?-hydroxyboronate esters by a Cu-catalyzed diboration/Matteson homologation sequence.

ABSTRACT: The copper-catalyzed diboration of aldehydes was used in conjunction with the Matteson homologation, providing the efficient synthesis of ?-hydroxyboronate esters. The oxygen-bound boronate ester was found to play a key role in mediating the homologation reaction, which was compared to the ?-hydroxyboronate ester (isolated hydrolysis product). The synthetic utility of the diboration/homologation sequence was demonstrated through the oxidation of one product to provide a 1,2-diol.

SUBMITTER: Moore CM

PROVIDER: S-EPMC4260635 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Facile formation of β-hydroxyboronate esters by a Cu-catalyzed diboration/Matteson homologation sequence.

Moore Cameron M CM Medina Casey R CR Cannamela Peter C PC McIntosh Melissa L ML Ferber Carl J CJ Roering Andrew J AJ Clark Timothy B TB

Organic letters 20141120 23

The copper-catalyzed diboration of aldehydes was used in conjunction with the Matteson homologation, providing the efficient synthesis of β-hydroxyboronate esters. The oxygen-bound boronate ester was found to play a key role in mediating the homologation reaction, which was compared to the α-hydroxyboronate ester (isolated hydrolysis product). The synthetic utility of the diboration/homologation sequence was demonstrated through the oxidation of one product to provide a 1,2-diol. ...[more]

PMID: 25412356

Similar Datasets

β-Silyloxy Allylboronate Esters through an Aldehyde Borylation/Homologation Sequence.

Project description:The areas of carbonyl borylation and the homologation of carbon-boron bonds have provided a number of fruitful methods in organic synthesis. Combining these approaches, the homologation of α-oxyboronate esters, provides pathways to access complex organoboronate esters stereoselectively. To this end, the homologation of α-silyloxyboronate esters with lithiated allyl chlorides to form β-silyloxy allylboronate esters is reported. Direct oxidation of the homologation products provides β-silyloxy allyl alcohols in good yield. The homologation provides a range of allylic alcohols, albeit with low diastereoselectivity.

| S-EPMC7351078 | biostudies-literature

Cu-Catalyzed Cross-Coupling of Benzylboronic Esters and Epoxides.

Project description:A reaction between epoxides and benzylboronic acid pinacol esters is described. CuI was found to be an effective catalyst of this transformation upon activation of the benzylboronic ester with an alkyllithium reagent. The reaction was very efficient and a variety of substituted epoxides were found to be good substrates with good regioselectivity for substitution at the less substituted side of the epoxide. A reaction using an enantioenriched secondary benzylboronic ester was found to not be stereospecific.

| S-EPMC8516127 | biostudies-literature

Synthesis of Functionalized Hydrazines: Facile Homogeneous (N-Heterocyclic Carbene)-Palladium(0)-Catalyzed Diboration and Silaboration of Azobenzenes.

Project description:The bis(N-heterocyclic carbene)(diphenylacetylene)palladium complex [Pd(ITMe)2(PhC≡CPh)] (ITMe=1,3,4,5-tetramethylimidazol-2-ylidene) acts as a highly active pre-catalyst in the diboration and silaboration of azobenzenes to synthesize a series of novel functionalized hydrazines. The reactions proceed using commercially available diboranes and silaboranes under mild reaction conditions.

| S-EPMC5215626 | biostudies-literature

Unraveling the Homologation Reaction Sequence of the Zeolite-Catalyzed Ethanol-to-Hydrocarbons Process.

Project description:Although industrialized, the mechanism for catalytic upgrading of bioethanol over solid-acid catalysts (that is, the ethanol-to-hydrocarbons (ETH) reaction) has not yet been fully resolved. Moreover, mechanistic understanding of the ETH reaction relies heavily on its well-known "sister-reaction" the methanol-to-hydrocarbons (MTH) process. However, the MTH process possesses a C1 -entity reactant and cannot, therefore, shed any light on the homologation reaction sequence. The reaction and deactivation mechanism of the zeolite H-ZSM-5-catalyzed ETH process was elucidated using a combination of complementary solid-state NMR and operando UV/Vis diffuse reflectance spectroscopy, coupled with on-line mass spectrometry. This approach establishes the existence of a homologation reaction sequence through analysis of the pattern of the identified reactive and deactivated species. Furthermore, and in contrast to the MTH process, the deficiency of any olefinic-hydrocarbon pool species (that is, the olefin cycle) during the ETH process is also noted.

| S-EPMC6519145 | biostudies-literature

Copper-catalyzed cascade reactions of α,β-unsaturated esters with keto esters.

Project description:A copper-catalyzed cascade reaction of α,β-unsaturated esters with keto esters is reported. It features a copper-catalyzed reductive aldolization followed by a lactonization. This method provides a facile approach to prepare γ-carboxymethyl-γ-lactones and δ-carboxymethyl-δ-lactones under mild reaction conditions.

| S-EPMC4362015 | biostudies-literature

Regio- and Stereoselective Synthesis of 1,1-Diborylalkenes via Bronsted Base-Catalyzed Mixed Diboration of Alkynyl Esters and Amides with BpinBdan.

Project description:The NaOtBu-catalyzed mixed 1,1-diboration of terminal alkynes using the unsymmetrical diboron reagent BpinBdan (pin = pinacolato; dan = 1,8-diaminonaphthalene) proceeds in a regio- and stereoselective fashion affording moderate to high yields of 1,1-diborylalkenes bearing orthogonal boron protecting groups. It is applicable to gram-scale synthesis without loss of yield or selectivity. The mixed 1,1-diborylalkene products can be utilized in Suzuki-Miyaura cross-coupling reactions which take place selectivly at the C-B site. DFT calculations suggest the NaOtBu-catalyzed mixed 1,1-diboration of alkynes occurs through deprotonation of the terminal alkyne, stepwise addition of BpinBdan to the terminal carbon followed by protonation with tBuOH. Experimentally observed selective formation of (Z)-diborylalkenes is supported by our theoretical studies.

| S-EPMC7187442 | biostudies-literature

Enantioselective palladium-catalyzed diboration of 1,1-disubstituted allenes.

Project description:A practical and enantioselective palladium-catalyzed diboration of 1,1-disubstituted allenes is developed by employing a P-chiral monophosphorus ligand, BI-DIME. A series of diboronic esters containing a chiral tertiary boronic ester moiety are formed in excellent yields and ee's with the palladium loading as low as 0.2 mol%. DFT calculations revealed a concerted mechanism of oxidative addition of bis(pinacolato)diboron and allene insertion, as well as a critical dispersion effect on the origins of the enantioselectivity. The method is successfully applied to the concise and enantioselective synthesis of brassinazole.

| S-EPMC5615263 | biostudies-literature

Rapid Cu-Catalyzed [211At]Astatination and [125I]Iodination of Boronic Esters at Room Temperature.

Project description:Access to 211At- and 125I-radiolabeled compounds in excellent RCCs and RCYs was achieved in just 10 min at room temperature using a Cu catalyst. The reaction conditions are applicable to a broad class of aryl and heteroaryl boronic reagents with varying steric and electronic properties as well as late-stage astatination and iodination of anticancer PARP inhibitors. This protocol eliminates the traditional need for toxic organotin reagents, elevated temperatures, and extended reaction times, providing a more practical and environmentally friendly approach to developing ?-emitting radiotherapeutics.

| S-EPMC5973503 | biostudies-literature

Ni(0)-catalyzed 1,4-selective diboration of conjugated dienes.

Project description:A catalytic stereoselective 1,4-diboration of conjugated dienes with B(2)(pin)(2) was accomplished with Ni(cod)(2) and PCy(3) as the catalyst. This reaction broadens the substrate scope of current methods for catalytic diene diboration by including internal and sterically hindered dienes, and it proceeds efficiently at low catalyst loadings. The intermediate allylboronate was oxidized to the stereodefined allylic 1,4-diol.

| S-EPMC3086412 | biostudies-literature

Phosphine-catalyzed intramolecular ?-umpolung addition of ?-aminoalkylallenic esters: facile synthesis of 3-carbethoxy-2-alkyl-3-pyrrolines.

Project description:An array of N-tosylated ?-aminoalkylallenic esters was prepared and their cyclization under the influence of nucleophilic phosphine catalysts was explored. The ?-aminoalkylallenic esters were prepared through aza-Baylis-Hillman reactions or novel DABCO-mediated decarboxylative rearrangements of allenylic carbamates. Conversion of these substrates to 3-carbethoxy-2-alkyl-3-pyrrolines was facilitated through Ph(3)P-catalyzed intramolecular ?-umpolung addition.

| S-EPMC4128507 | 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