Acetoxy-Substituted Cyclopropane Dicarbonyls as Stable Donor–Acceptor–Acceptor Cyclopropanes

Stereoselective construction of nitrile-substituted cyclopropanes.

Nitrile-substituted cyclopropanes are readily synthesized in a stereocontrolled fashion from the intermolecular cyclopropanation between 2-diazo-2-phenylacetonitrile and electron-rich olefins, catalyzed by the chiral dirhodium complex, Rh(2)(S-PTAD)(4).

Synthesis of Trifluoroacetyl‐Substituted Cyclopropanes Using Onium Ylides

The use of carbonyl-stabilized ammonium- and sulfonium ylides allows for the synthesis of highly-functionalized trifluoroacetyl-substituted cyclopropanes. It turned out that the diastereoselectivities strongly depend on the nature of the chosen ylide and the employed base. The products could be obtained in good yields under operationally simple conditions.

Cyclization and annulation reactions of nitrogen-substituted cyclopropanes and cyclobutanes.

Cyclization and annulation reactions initiated by ring-opening of small rings, especially cyclopropanes and cyclobutanes are now well-established in synthetic chemistry. Nevertheless, the potential of aminocyclopropanes and cyclobutanes, an important subclass for the synthesis of nitrogen-rich building blocks, has remained unexploited for a long time, despite important pioneering results. In th...

Highly enantioselective and diastereoselective cycloaddition of cyclopropanes with nitrones and its application in the kinetic resolution of 2-substituted cyclopropane-1,1-dicarboxylates.

Homoconjugation in Radical Cations

Recent studies of nuclear spin polarization effects in cyclopropane derivatives have provided considerable information on the structure as well as the spin and charge density distributions in this class of radical ca,tions. In the present work we report an extension of the frontier MO/perturbation MO theory of homoconjugation to include such species in an attempt to rationalize further the expe...