Α-hydroxylation Of Ketones Research Articles

Facile Approach to Preparing Microporous Organic Polymers through Benzoin Condensation

A series of microporous organic networks linked by α-hydroxyl ketone were synthesized based on benzoin self-condensation of multiformyl-containing building blocks. Fourier transform infrared and solid-state (13)C CP/MAS NMR spectroscopy were utilized to confirm the α-hydroxyl ketone linkage of the obtained polymers. The hollow microspheric morphology can be observed from scanning electron microscopy and transmission electron microscopy images. The materials, with Brunauer-Emmet-Teller specific surface area up to 736 m(2) g(-1), possess a hydrogen storage capacity up to 1.42 wt % at 77 K and 1.0 bar and a carbon dioxide uptake up to 15.3 wt % at 273 K and 1.0 bar. These excellent characteristics would make them become promising candidates for gas storage.

A highly active organocatalyst for the asymmetric α-aminoxylation of aldehydes and α-hydroxylation of ketones

Enantiopure trans-3-trifluoromethylsulfonylamino-4-silyloxypyrrolidines efficiently catalyse the asymmetric α-aminoxylation of aldehydes. At 1% catalyst loading (solvent-free conditions) or at 2% catalyst loading (acetonitrile solution) aldehydes are completely converted in short reaction times leading to α-aminoxylation products with very high (96–99%) enantioselectivity.

ChemInform Abstract: N‐Heterocyclic Carbene Catalyzed Intramolecular Crossed Aldehyde—Ketone Benzoin Condensation in the Chalcone of o‐Phthalaldehyde: A Facile Synthesis of Naphthalenones.

Abstract The intramolecular crossed aldehyde–ketone benzoin condensation in the chalcone of o -phthalaldehyde (OPA) catalyzed by N -heterocyclic carbene (NHCs) generated in situ from readily available imidazolium and thiazolium salts is described. In this reaction, bicyclic α-hydroxyl ketones (naphthalenone type tertiary alcohol) were selectively produced in good yields (75–94%) in shorter reaction times (20 min) through nucleophilic addition of acyl anion generated by umpolung in OPA–chalcone (regio controlled).

N-Heterocyclic carbene catalyzed intramolecular crossed aldehyde–ketone benzoin condensation in the chalcone of o-phthalaldehyde: a facile synthesis of naphthalenones

The intramolecular crossed aldehyde–ketone benzoin condensation in the chalcone of o-phthalaldehyde (OPA) catalyzed by N-heterocyclic carbene (NHCs) generated in situ from readily available imidazolium and thiazolium salts is described. In this reaction, bicyclic α-hydroxyl ketones (naphthalenone type tertiary alcohol) were selectively produced in good yields (75–94%) in shorter reaction times (20 min) through nucleophilic addition of acyl anion generated by umpolung in OPA–chalcone (regio controlled).

ChemInform Abstract: Synthetic Use of Poly[4-(diacetoxyiodo)styrene] for Organic Reactions.

Poly[4-(diacetoxyiodo)styrene] is sufficiently reactive for the iodination of aromatics, the oxidative 1,2-aryl migration of alkyl aryl ketones, the α-hydroxylation of ketones, and the oxidation of...

Xylogranatins A—D: Novel Tetranortriterpenoids with an Unusual 9,10‐seco Scaffold from Marine Mangrove Xylocarpus granatum

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

Efficient and Mild Benzoin Condensation Reaction Catalyzed by Simple 1‐N‐Alkyl‐3‐methylimidazolium Salts.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Efficient and mild benzoin condensation reaction catalyzed by simple 1- N-alkyl-3-methylimidazolium salts

The benzoin reaction, catalyzed by simple 1- N-alkyl-3-methylimidazolium salt-based ionic liquid via carbene intermediate, to give the α-hydroxyl ketone proceeds in CH 2Cl 2 under mild conditions.

α‐Hydroxylation of Carbonyls Using Iodine.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Water-promoted direct aerobic oxidation of enol silyl ether to α-hydroxyl ketones without catalyst

Clean oxidation of aromatic silyl enol ethers in water by air without the use of any catalyst generates α-hydroxyl ketones in good yields (69–86%).

α-Hydroxylation of carbonyls using iodine

The α-hydroxylation of ketones and aldehydes to α-hydroxyketals mediated by iodine under basic conditions in MeOH is described. Enolates generated under the reaction conditions are iodinated and the resulting α-iodocarbonyl is transformed into the hydroxyketal. The use of iodine for this chemistry represents an economical and practical alternative to existing methods for this transformation.

Synthetic Use of Poly[4-(diacetoxyiodo)styrene] for Organic Reactions

Abstract Poly[4-(diacetoxyiodo)styrene] is sufficiently reactive for the iodination of aromatics, the oxidative 1,2-aryl migration of alkyl aryl ketones, the α-hydroxylation of ketones, and the oxidation of hydroquinones and sulfides similarly to (diacetoxyiodo)benzene. Here, those reactions with poly[4-(diacetoxyiodo)styrene] are very useful because of the simple operation; thus, filtration gives the crude products and recovered poly(4-iodostyrene), and then poly[4-(diacetoxyiodo)styrene] can be regenerated by oxidation of the recovered poly(4-iodostyrene), which are reused for the same reactions.

Total chiral synthesis of azole antifungals via α-hydroxylation of ketones

The use of camphorsulfonyl oxaziridines for the preparation of 2′,4′-difluoro-(R)-2-hydroxypropiophenone, ( 2), a key intermediate for the synthesis of azole antifungals Sch 42427 and ER-30346 ( 1) in excellent enantiomeric excess and high chemical yield is described.

Facile Synthesis of α- Keto Carbonyl Compounds by Indirect Anodic Oxidation

Abstract Secondary alcohols having a carbonyl group at the neighboring carbon atom were electrochemically oxidized to the corresponding α-keto carbonyl compounds in good yields. Thus, aromatic α-hydroxyl esters were easily transformed to arylglyoxylates in excellent yields using an undivided cell while efficient anodic oxidation of α-hydroxyl ketones and aliphatic α-hydroxyl esters successfully proceeded in a divided cell to give the corresponding α-keto carbonyl compounds.

α-Hydroxylation of ketones using o-iodosylbenzoic acid

-o-Iodosylbenzoic acid (KOH/CH 3OH) converts various ketones to α-hydroxydimethyl-acetals in high yield with the advantageous feature of solubility of the reduction product o-iodobenzoic acid under the basic reaction conditions thus allowing isolation of the oxidation product by simple CH 2Cl 2 extraction.

α-Hydroxylation of ketones: Osmium tetroxide/N-methylmorpholine-N-oxide oxidation of silyl enol ethers

Osmium tetroxide/N-methylmorpholine-N-oxide oxidation of silyl enol ethers, derived from ketones with either kinetic or thermodynamic regiochemical control, produces α-ketols in good to excellent yields.