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Max Malacria

Publications and source records attributed to Max Malacria.

43 records · Page 3Linked to original sources
PubMed2002

Stereoselective transition metal-catalyzed and radical polycyclizations.

This short review presents a selection of metal-mediated and radical polycyclizations reported during the past two years. Palladium-catalyzed domino processes, cobalt-mediated cycloadditions and Pauson-Khand reactions catalyzed by rhodium are described. Ruthenium and platinum are shown as powerful metal catalysts in cyclizations, ring-closing metathesis and cycloisomerizations. Finally, recent examples of radical cascades, and their synthetic applications, are selected for their ability to build polycyclic compounds.

Animals↗
PubMed1999

5-Endo-Trig Radical Cyclizations of Bromomethyldimethylsilyl Diisopropylpropargylic Ethers. A Highly Diastereoselective Access to Functionalized Cyclopentanes.

An efficient radical sequence involving a 5-exo-dig, a diastereoselective 1,5-H transfer, and a rarely observed in an all-carbon system 5-endo-trig cyclization allows the construction of cyclopentyl derivatives 2 bearing four controlled stereogenic centers from diisopropyl precursors 1. Olefins 3 were also isolated as minor side products. The effect of the acetylenic substituent Y has been investigated, and the scope and the limitations of the cascade have been delineated.

Journal Article↗
PubMed1999

Study of a Radical Cyclizations Cascade Leading to Bicyclo[3.1.1]heptanes.

An efficient radical cascade involving a 5-exo-dig, a 1,6-H transfer, a 6-endo-trig, a 4-exo-dig, and a final 1,6-H transfer allows the diastereoselective construction of bicyclo[3.1.1]heptanes. The size of the R substituent at the propargylic position governs the diastereoselectivity of the 6-endo-trig step. Other parameters (acetylenic substituents, unsaturated partners,.) have been investigated, and the scope and the limitations of the cascade have been delineated.

Journal Article↗
PubMed1996

New Cobalt-Catalyzed Cycloisomerization of epsilon-Acetylenic beta-Keto Esters. Application to a Powerful Cyclization Reactions Cascade.

The full details of investigations into the cobalt(I)-catalyzed ene type reaction of epsilon-acetylenic beta-keto esters to form highly functionalized methylenecyclopentanes are described. The observed regio-, chemo-, and stereoselectivities support a process of cycloisomerization which controls the relative stereochemistry of two contiguous stereogenic centers. An efficient route to the basic skeleton of the phyllocladane family has been achieved via a one-pot sequence of cyclizations: ene type, [2 + 2 + 2], [4 + 2]. This new cascade created six carbon-carbon bonds and four rings in a totally stereoselective manner from an easily accessible acyclic polyunsaturated precursor.

Journal Article↗