A Novel Route to Isoannulated Heteroaromatic Compounds. Part 2. The Dipole Route to Furo/Thieno Pyrroles and α-Pyridones, and Their Benzo Derivatives.-A new methodology, involving 1,7-dipolar cyclizations of conjugated dipoles followed by a multistep rearrangement affording ring-contracted products is employed for the synthesis of various examples of the title compounds. As demonstrated for (IV) and (V) the reaction starts with the alkynylcarbaldehydes (I) which are converted into nitrones such as (III). In some cases beside the Z isomers 3-10% of the E isomers are obtained. Under different thermolysis conditions the nitrones are converted into the pyrroles and α-pyridones. The product distribution is strongly influenced by the nature of the terminal alkynyl substituent. The derivatives (V) are not stable. They react with oxygen to the imides (VI). The benzo-analogues are more stable, some Diels-Alder reactions of them are demonstrated. -(BUSSENIUS, J.; LABER, N.; MUELLER, T.; EBERBACH, W.; Chem.
Amines Q 0120Markownikoff and anti-Markownikoff Hydroamination with Palladium Catalysts Immobilized in Thin Films of Silica Supported Ionic Liquids. -The concept of immobilizing organometallic complexes in a thin film of supported ionic liquids is utilized to synthesize novel bifunctional catalysts combining soft Lewis acidic and strong Broensted acidic functions. The materials exhibit exceptional catalytic activity for the addition of aniline (II) to styrene (I), providing the Markownikoff product (III) under kinetically controlled conditions and mainly the anti-Markownikoff product (IV) in the thermodynamic regime. -(JIMENEZ, O.; MUELLER*, T. E.; SIEVERS, C.; SPIRKL, A.; LERCHER, J. A.; Chem.
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