A practical procedure for the synthesis of multifunctional aldehydes through the Fukuyama reduction and elucidation of the reaction site and mechanism

A highly efficient heterogeneous Pd/C catalyst D1 was found to effect the reduction of thiol esters 1 to the corresponding aldehydes 2 with such a low catalyst loading as 0.5-1.0 mol %. The chemical properties of the Pd/C catalysts together with the XRF analysis reveal that the reduction is most likely to proceed on the solid surface of the Pd/C catalyst rather than in the solution phase outside the pores. A reaction mechanism through oxidative addition of Pd to the thiol esters 1 was postulated by detection of the oxidative addition intermediate by React IR analysis. A practical purification of 2 was accomplished by conversion to water-soluble bisulfite adducts 7.     

A novel pyrrole synthesis via reaction of ketones with N-aminoimides

A new, mild synthesis of pyrroles using N-aminoimides and a ketone is described. The reaction has been utilized in the synthesis of dimeric morphinans containing a connecting pyrrole ring. The reaction appears to proceed through a diacylhydrazone intermediate, and it is suggested that the driving force behind the reaction is the facility with which a protonated imide moiety operates as a leaving group.     

Synthesis of diaryl ketones via a phosphine-free Fukuyama reaction

The synthesis of unsymmetrical diaryl ketones via the Fukuyama coupling of thioesters and organozinc reagents is described. Typically, the synthesis of diaryl ketones using this methodology provides low yields. The simple complex, Pd(dba)(2), was found to convert a variety of aryl thioesters to diaryl ketones in good yields.     

A highly regioselective synthesis of 2-aryl-6-chlorobenzothiazoles employing microwave-promoted Suzuki-Miyaura coupling reaction

Suzuki-Miyaura coupling reactions of 2,6-dichlorobenzothiazole with arylboronic acids, promoted by microwave heating, efficiently produce 2-aryl-6-chlorobenzothiazoles in a highly regioselective manner. This process serves as the foundation for a simple method to rapidly construct 2-aryl-6-chlorobenzothiazole libraries.     

A novel route for synthesis of gamma-butyrolactone through the coupling of hydrogenation and dehydrogenation

A coupling process of the hydrogenation of maleic anhydride and the dehydrogenation of 1,4-butanediol has been invented for the synthesis of gamma-butyrolactone over a Cu-Zn catalyst, realizing optimal hydrogen utilization and better energy efficiency.     

A novel synthesis of perfluoroalkyl alkyl ketones

A novel synthesis of perfluoroalkyl alkyl ketones via the hydrolysis of fluorinated β-ketophosphonium salts is described. In view of the fact that a one-pot reaction without isolation of intermediates and the total yield in 2 steps reaches 37-78%, the present method provides a convenient synthesis of the title compounds.     

A base-mediated three-component coupling reaction for the synthesis of phosphorohydrazones

A simple and efficient three-component coupling reaction for the synthesis of phosphorohydrazones was developed. Both aldehydes and ketones participated in the reaction to afford the corresponding phosphorohydrazones in moderate-to-good yields. Moreover, a novel P–N ligand was synthesized by this method, which can act as a fluorescent sensor for iron ion.     

The reaction of malononitrile with thioglycolic acid. A novel procedure for the synthesis of thiazolone derivatives

Malononitrile (I) reacted with thioglycolic acid to yield the thiazolin-4-one derivatives II or III depending on the molar ratio of the reactants. Compound II reacted with benzaldehyde in refluxing pyridine to yield the arylidene derivative IV. On the other hand, the benzylidine bis derivative VIII was obtained when II was reacted with benzaldehyde in refluxing ethanol. The structure of IV was established via its synthesis from the reaction of benzylidenemalononitrile (VI) and thioglycolic acid in refluxing acetic acid. Similar to II, compound III condensed with benzaldehyde to yield the benzylidene derivative IX.     

由酮合成对称二烃基二硒醚的新方法

在正丁胺的催化下, 酮与硒氢化钠, 二硒化钠乙醇溶液通过"一锅"法反应得到了中等产率的二硒醚.     

A novel stereocontrolled synthesis of 1,2-trans cyclopropyl ketones via suzuki-type coupling of acid chlorides with cyclopropylboronic acids

[reaction: see text] The palladium-catalyzed cross-coupling reaction of cyclopropylboronic acids with acyl chlorides was achieved by the combination of Ag(2)O and K(2)CO(3) as the base. Highly enantiomerically enriched cyclopropyl ketones (ee >90%) were also obtained by the reaction of corresponding chiral cyclopropylboronic acids.     

A novel aza-Prins-Friedel-Crafts reaction for the synthesis of 4-arylpiperidines

Aldehyde, homoallylic amine and arene undergo smooth cyclization in the presence of BF₃·OEt₂ to afford 4-arylpiperidines in good yields and with high trans-selectivity. This is the first report on the preparation of 4-arylpiperidines via aza-Prins-Friedel-Crafts reaction.     

A novel four-component reaction for the synthesis of functionalised dihydropyrimidines

In a multi-component reaction (MCR) of a phosphonate, nitriles, aldehydes and isocyanates, N3-functionalised dihydropyrimidines can be synthesised efficiently via a Horner-Emmons/aza Diels-Alder pathway.     

A new method for the synthesis of dithiocarbamates by CuI-catalyzed coupling reaction

The Ullmann-type coupling reaction of sodium dithiocarbamates with aryl iodides and vinyl bromides catalyzed by CuI/N,N-dimethylglycine proceeds smoothly in DMF at 110 °C to give corresponding dithiocarbamates in good yields.     

Library-friendly synthesis of fluorinated ketones through functionalized hydration of alkynes and investigation of the reaction mechanism

A library-friendly synthesis of α-substituted-α-fluoroketones through functionalized hydration of alkynes in one pot under mild conditions is reported. The ready availability of alkynes and organoboronic acids makes this reaction quite attractive. We also studied the key intermediate—a fluorinated cationic gold species—using in situ NMR spectroscopy and ESI-high resolution mass spectrometry.     

A novel and efficient synthesis of fluoroalkylated multifunctional 1,2,3,4-tetrahydropyrimidines

Fluoroalkylated multifunctional 1,2,3,4-tetrahydropyrimidines were synthesized in almost quantitative yields for the first time by the reaction of 3-fluoroalkyl-3-anilinoacrylic acid esters with primary amines and formaldehyde under mild conditions.     

A novel one-pot procedure for the synthesis of stable dioxadiazastannepines and dioxadiazasilepines

A novel synthetic approach to seven-membered silicon- and tin-containing heterocycles has been developed. 5,6-Diaryl-1,3,4,7,2-dioxadiazastannepines 3a-l and 5,6-diaryl-1,3,4,7,2-dioxadiazasilepines 4a-l were prepared in one pot from vicinal dioximes 1a-d and diorganodichlorostannanes and diorganodichlorosilanes via dianion intermediate 2 in good yields.     

Green synthesis of novel chalcone and coumarin derivatives via Suzuki coupling reaction

Chalcones and coumarins are important naturally occurring plant constituents and display a wide range of pharmacological and biological activities. In an environmentally benign approach, synthesis of biphenyl chalcone and coumarin derivatives was successfully accomplished via Suzuki coupling by using PEG-400 as a solvent under microwave irradiation. Salient feature of this methodology includes: short reaction time, good to excellent yields, and prominent tolerance of different functional groups.