Saccharomyces cerevisiae catalyzed one-pot three component synthesis of 2,3-diaryl-4-thiazolidinones

Saccharomyces cerevisiae (baker’s yeast) catalyzed one-pot three component cyclocondensation of aryl aldehydes, amines, and thioglycolic acid in organic medium leading to 2,3-diaryl 4-thiazolidinones has been carried out for the first time.     

Copper-catalyzed aryl amination in aqueous media with 2-dimethylaminoethanol ligand

Copper-catalyzed amination of aryl bromides and iodides under mild conditions has been developed with 2-dimethylaminoethanol as ligand and water as solvent. A variety of hydrophilic and hydrophobic aryl halide substrates have been aminated in good yield with a variety of amino acids, amino alcohols and peptides. This method has successfully N-arylated some hydrophilic amino compounds not available by other methods.     

Reeve's synthesis of 2-imino-4-thiazolidinone from alkyl (aryl) trichloromethylcarbinol revisited, a three-component process from aldehyde, chloroform and thiourea

An efficient synthesis of 2-imino-4-thiazolidinones from readily accessible alkyl (aryl) trichloromethylcarbinols and thioureas under mild conditions is reported. A one-pot three-component synthesis of the title compounds from aldehyde, chloroform and thiourea is also developed for the first time     

Ionic Liquid–Mediated,One-Pot Synthesis for 4-Thiazolidinones

A convenient one-pot, three-component cyclocondensation mediated by ionic liquid for obtaining 2,3-disubstituted-4-thiazolidinones with excellent yields is reported.     

β-Arylation of Racemic Secondary Benzylic Alcohols to Access Enantioenriched β-Arylated Alcohols

The transformation of alcohols into value-added products is of great importance, as simple alcohols are widespread and can be easily derived from both fossil fuels and biomass. The selective functionalization of a sp³ C−H bond on the alkyl side chain of an alcohol over its hydroxyl group would offer an expedient route to expand the chemical space of alcohols but it remains a challenging task. Harnessing the borrowing hydrogen strategy, the β-arylation of secondary alcohols with aryl bromides has been achieved in this study, which allows for the selective functionalization of a β-Csp³−H bond in an alcohol substrate. Under the catalysis of a Pd complex, secondary alcohols reacted with aryl bromides to afford 1,2-diaryl alcohols with broad substrate scope in the presence of a ketone additive. Furthermore, the enantioconvergent version of the reaction has also been realized, transforming racemic secondary alcohols into enantioenriched chiral 1,2-diaryl alcohols under the cooperative Pd and Ru catalysis. Mechanism studies indicate that the reactions are enabled by borrowing hydrogen catalysis.     

Reaction of vinyloxyalkylamines with mercaptoacetic acid

N-[2(3)-Hydroxyalkylj-4-thiazolidinones have been synthesized by the reaction of 2(3)-vinyloxyalkylamines with mercaptoacetic acid in 24–69 % yield. The structure of the compounds obtained was supported by (R and¹H NMR spectroscopic data.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 677–679, March, 1996.     

Copper‐Catalyzed One‐Pot Trifluoromethylation/Aryl Migration/Carbonyl Formation with Homopropargylic Alcohols

A novel copper‐catalyzed one‐pot functionalization of homopropargylic alcohols that involves trifluoromethylation, aryl migration, and formation of a carbonyl moiety has been developed. This reaction constitutes the first direct conversion of homopropargylic alcohols into CF₃‐containing 3‐butenal or 3‐buten‐1‐one derivatives in a regioselective manner. Mechanistic studies indicate that the 1,4‐aryl migration proceeds through a radical pathway.     

An efficient synthetic route for quinazolinyl 4-thiazolidinones

An efficient solvent-free cyclocondensation route for condensing mercaptoacetic acid with quinazolinyl-substituted azomethines has been developed using silica chloride as a catalyst for obtaining heteryl-substituted 4-thiazolidinones. The route is found to be rapid, relatively economical, and eco-friendly. The precursors, quinazolinyl azomethines have been obtained in multisteps starting from quinazolinone.     

FeCl3催化Et2Zn与芳香醛的加成反应研究

以FeCl_3作为催化剂, 研究了Et_2Zn与芳香醛的加成反应, 考察了催化剂、溶剂、催化剂与Et_2Zn用量及温度对该反应的影响. 实验结果表明: 在60℃, 1.2当量Et_2Zn, 甲基环戊基醚为溶剂的反应条件下, 10 mol% FeCl_3可以较高效的将各种芳香醛转化为仲醇.     

One‐Pot Synthesis of Allylic Sulfones,Ketosulfones, and Triflyl Allylic Alcohols from Domino Reactions of Allylic Alcohols with Sulfinic Acid under Metal‐Free Conditions

A metal‐free tandem procedure by using a sulfonylation reaction of aryl allylic alcohols followed by an iodobenzenediacetate (PIDA)‐promoted oxidative functionalization has been established. Allylic sulfones, γ‐ketosulfones, and triflyl allylic alcohols have been constructed in a single operation. The methodology incorporates the sulfonyl (both aryl and triflyl) functionality with a simple work‐up procedure.     

Kinetic and selectivity control of TEMPO electro-mediated oxidation of alcohols

TEMPO electro-mediated oxidation of alcohols has been investigated in aqueous and hydro-organic media. Mono- and poly-saccharides, aryl alcohols and heterocyclic alcohols were converted into the corresponding carbonyls in good chemical and Faradaic yields. In both solvents, the electrochemically generated TEMPO⁺ was used in catalytic amount and the kinetics was found to be controlled by the diffusion step.     

Organosoluble copper clusters as precatalysts for carbon-heteroelement bond-forming reactions: microwave and conventional heating

The coupling of aryl iodides with alcohols under mild conditions has been explored using self-assembled octanuclear copper clusters as catalysts. Reactions involving tetrahydrofurfuryl alcohol were typically complete in 4-8 h at 110 degrees C using an oil bath or 1-3 h with microwave heating. High yields of alkyl aryl ethers were obtained with catalyst loadings as low as 0.4 mol % cluster.     

Oxazolidine ring opening and isomerization to (E)-imines. Asymmetric synthesis of aryl-alpha-fluoroalkyl amino alcohols

[reaction: see text] A base-induced ring opening/imine isomerization/diastereoselective organometallic addition sequence on 4-substituted 2-perfluoroalkyl-1,3-oxazolidines has been developed for the asymmetric synthesis of aryl alpha-perfluoroalkylamine derivatives. This practical method provides chiral amino alcohols in 60-95% yield with uniformely high diastereoselectivities ranging from 35:1 to >100:1.     

An expedient route for the reduction of carboxylic acids to alcohols employing 1-propanephosphonic acid cyclic anhydride as acid activator

A simple and efficient method for the synthesis of alcohols from the corresponding carboxylic acids is described. Activation of carboxylic acid with 1-propanephosphonic acid cyclic anhydride (T3P) and subsequent reduction using NaBH₄ yield the alcohol in excellent yields with good purity. Reduction of several alkyl/aryl carboxylic acids and N^α-protected amino acids/peptide acids as well as N^β-protected amino acids was successfully carried out to obtain corresponding alcohols in good yields. All the products were fully characterized by ¹H NMR and mass spectral analyses. The procedure is mild, simple and the isolation of the products is easy.     

Enantioselective addition of diethylzinc to aldehydes catalyzed by 3,3′‐bis(2‐oxazolyl)‐1,1′‐bi‐2‐naphthol (BINOL‐Box) ligands derived from 1,1′‐bi‐2‐naphthol

With 3,3′‐bis(2‐oxazolyl)‐1,1′‐bi‐2‐naphthols (BINOL‐Box) synthesized from 1,1′‐bi‐2‐naphthol (BINOL), the enantioselective addition of diethylzinc to aryl aldehydes proceeded smoothly to give secondary aryl alcohols in good yield with good enantioselectivity. Interestingly, the yields and enantioselectivities were affected by the mixing sequence of the reactants. Furthermore, the synthesis of both enantiomers of the addition products has been achieved using the same ligands by choosing achiral additives, Ti(O‐iPr)₄ and 4A molecular sieves. Copyright © 2000 John Wiley & Sons, Ltd.     

I2/Fe(NO3)3·9H2O-catalyzed oxidative synthesis of aryl carboxylic acids from aryl alkyl ketones and secondary benzylic alcohols

An interesting and convenient procedure for the oxidative transformation of aryl alkyl ketones and secondary benzylic alcohols to aryl carboxylic acids has been developed. By using iodine and Fe(NO₃)₃·9H₂O as the catalysts, DMSO and oxygen as the oxidants, the desired aryl carboxylic acids were synthesized in moderate to excellent yields (up to 91%).     

Cesium hydroxide-promoted aerobic oxidation of sec-aromatic alcohols

A CsOH-promoted aerobic oxidation of sec-aromatic alcohols has been developed, using air as a free and clean oxidant, and providing aryl ketones in good to excellent yields.     

Cobalt‐Catalyzed Intermolecular C(sp2)O Cross‐Coupling

Cobalt(II)‐catalyzed C(sp²)?O cross‐coupling between aryl/heteroaryl alcohols and vinyl/aryl halides in the presence of Cu^I has been achieved under ligand‐free conditions. In this reaction, copper plays a significant role in transmetalation rather than being directly involved in the C?O coupling. This unique Co/Cu‐dual catalyst system provides an easy access to a library of aryl–vinyl, heteroaryl–styryl, aryl–aryl, and heteroaryl–heteroaryl ethers in the absence of any ligand or additive.     

A single phosphine ligand allows palladium-catalyzed intermolecular co bond formation with secondary and primary alcohols

Forging a bond: An efficient, general palladium catalyst for C?O bond-forming reactions of secondary and primary alcohols with a range of aryl halides has been developed using the ligand 1. Heteroaryl halides, and for the first time, electron-rich aryl halides can be coupled with secondary alcohols. A diverse set of substrate combinations are possible with just a single ligand, thus obviating the need to survey multiple ligands.