A series of eight 3-oxapentane podand derivatives was successfully prepared based on the croton condensation reaction from 1,5-bis(aryl)-1,5-dithia-3-dioxadecane and 1,5-bis(aryl)-1,3,5-trioxadecane with bezaldehyde or acetophenone in acidic condition. These synthesized have structure acyclic crown rings inserted by polyether polythiaether chain vinyl ketone conjugated aryl group. Therefore, th...

2-Chloroquinoline-3-carbaldehyde 1 reacts with 2-cyanoacetohydrazide in ethanol to result in 1-[1-aza-2-(2-chloro(3quinolyl))vinyl]-2-cyanoacetamide 2. Phenyl isothiocyanate added to a stirred solution of compound 2, sulphur and triethylamine in a mixed solvent of dimethylformamide : ethanol to result in N-[1-aza-2-(2-chloro(3-quinolyl))vinyl](4amino-3-phenyl-2-thioxo(1,3-thiazoline-5-yl)) carb...

Redox-neutral tetrafluoroethylation of aryl alkynes with 1,1,2,2-tetrafluoroethane sulfonic acid leading to α-tetrafluoroethylated acetophenones is described in the Full Paper by Takuji Kawamoto and co-workers on page 9529 ff. The reaction proceeds via formation vinyl tetrafluoroethanesulfonates followed a radical tetrafluoroethylation.

poly (vinylpyrrolidone)-grafted silica as an organic-inorganic hybrid material was used as an effective heterogeneous polymeric cosolvent catalyst in organic reactions. this modified silica catalyzed nucleophilic displacement of alkyl halides for easy preparation of alkyl thiocyanates, alkyl cyanides, alkyl azides and alkyl aryl ethers. furthermore, the catalyst was applied for the conversion o...

Transition-metal hydrides generate α-alkoxy radicals by H• transfer to enol ethers. We have measured the rate constant for transfer from CpCr(CO)3H to n-butyl vinyl ether and have examined the chemistry of radicals generated by such transfers. Radicals from appropriate substrates undergo 5-exo cyclization, with higher diastereoselectivity than the analogous all-carbon radicals. From such radica...

Merging is the game! The coupling of a domino reaction and an internal neutral redox reaction constitutes an excellent manifold for the stereoselective synthesis of di- and trisubstituted olefins featuring a malonate unit, an ester, or a free carboxylic acid as substituents at the allylic position (see scheme; MW=microwave). The reaction utilizes simple starting materials (propargyl vinyl ether...

Tertiary propargyl vinyl ethers armed with an electron-withdrawing group (amide or ester) at the tertiary propargylic position have been efficiently transformed into trisubstituted C(2)-chain functionalized furans. The metal-free domino transformation involves a microwave-assisted tandem [3,3]-propargyl Claisen rearrangement/5-exo-dig O-cyclization reaction. The manifold can be performed in a o...

A comparative study of the Au(I)-catalyzed [3,3]-sigmatropic rearrangement of propargylic esters and propargyl vinyl ethers is described. Stereochemically defined cyclopropanes are employed as mechanistic probes to provide new synthetic and theoretical data concerning the reversibility of this type of rearrangement. Factors controlling the structure-reactivity relationship of Au(I)-coordinated ...

The generation of a small and representative library of 3,5,8-trisubstituted coumarins (21 compounds, 7 families, 3 groups) is described. The library was built from the corresponding propargyl vinyl ethers and three different 1,3-dicarbonyl derivatives using a one-pot coupled domino strategy. These coumarins constitute a novel chemotype defined by the presence of a chemical handle in the pyrano...