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Jean Rodriguez

Publications and source records attributed to Jean Rodriguez.

9 recordsLinked to original sources
PubMed2006

Synthetic studies on the MARDi cascade: stereoselective synthesis of heterocyclic seven-membered rings.

[reaction: see text] A versatile stereoselective synthesis of substituted and functionalized heterocyclic seven-membered rings is described. The approach involves a formal two-carbon ring expansion of heterocyclic cyclopentanones through a base-induced anionic domino three-component transformation named the MARDi cascade leading either to oxa-, aza-, or thiacycloheptanes bearing up to five contiguous stereogenic centers.

Journal Article↗
PubMed2006

Selective construction of carbocyclic eight-membered rings by ring-closing metathesis of acyclic precursors.

Although the efficient preparation of cyclooctanoids has remained a long-standing objective, a real breakthrough was possible only relatively recently with the development of more specific reagents and by the development of new reactions. The direct construction of carbocyclic eight-membered rings from acyclic precursors is still a challenge, mainly because of unfavorable entropic and enthalpic factors that preclude ring formation. This Minireview describes the utilization of ring-closing metathesis (RCM) as a new approach to synthesize cyclooctanoids.

Journal Article↗
PubMed2005

Multicomponent domino reaction from beta-ketoamides: highly efficient access to original polyfunctionalized 2,6-diazabicyclo[2.2.2]octane cores.

We describe a new multicomponent domino reaction from beta-ketoamides, involved as substrates and as nucleophilic partners. We obtain highly functionalized and original 2,6-diazabicyclo[2.2.2]octane cores (2,6-DABCO) in a five-step one-pot sequence, which is fast, environmentally friendly, operationally simple to manage, and combines step- and atom-economic aspects.

Journal Article↗
PubMed2005

Unique Michael addition-initiated domino reaction for the stereoselective synthesis of functionalized macrolactones from alpha-nitroketones in water.

[reaction: see text]. A unique domino reaction of alpha-nitrocycloalkanones with alpha-alkyl alpha,beta-unsaturated aldehydes in aqueous base was discovered, leading to the one-pot synthesis of hitherto unknown functionalized, bridged, bicyclic lactones containing 10-, 11-, 13-, and 15-membered rings. The structures of these heterocyclic compounds, containing also an unusual 6-hydroxy-1,2-oxazine ring, were determined by spectral and single-crystal X-ray diffraction studies.

Aldehydes↗
PubMed2004

Stereoselective synthesis of bicyclo[4.2.1]nonane skeletons by ring-closing metathesis: a new versatile methodology for the efficient assembly of functionalized cyclooctanoids.

[reaction: see text] A new versatile methodology, resulting in a formal three-carbon ring expansion of cyclopentanones, for the efficient assembly of functionalized cyclooctanoids is described. The approach is based on the chemo-, regio-, and stereoselective alpha,gamma-difunctionalization of beta-ketoesters followed by ring-closing metathesis to form functionalized bicyclo[4.2.1]nonanes, precursors of the corresponding cyclooctanes, by selective ring cleavage of the one-carbon-atom bridge.

Journal Article↗
PubMed2004

Unprecedented in situ oxidative ring cleavage of isoxazolidines: diastereoselective transformation of nitronic acids and derivatives into 3-hydroxymethyl 4-nitro tetrahydrofurans and pyrrolidines.

[reaction: see text] Nitronic acids undergo an intramolecular 1,3-dipolar cycloaddition to unactivated double bonds, and the resulting isoxazolidines spontaneously evolve by an unprecedented in situ oxidative ring cleavage. The extension of this transformation to silyl nitronates results in a general diastereoselective construction of hydroxymethyl nitro functionalized tetrahydro-furans and -pyrrolidine having up to four consecutive stereogenic centers.

Cyclization↗