Aminocarbonylation alkenes

As stated above, aliphatic amines are potent ligands for electrophilic transition metals and are efficient catalyst poisons in attempted alkene animation reactions. However, tosylation of the basic amino group greatly reduces its complexing ability, yet does not compromise its ability to nucleophilically attack complexed alkenes. Thus, a variety of alkenic tosamides efficiently cyclized under palladium(II) catalysis producing N-tosylenamines in excellent yield (equations 17 and 18).32 Again, this alkene amination proceeded through an unstable a-alkylpalladium(II) species, which could be intercepted by carbon monoxide, to result in an overall aminocarbonylation of alkenes. With ureas of 3-hydroxy-4-pentenyl-amines (Scheme 7), this palladium-catalyzed process was quite efficient but it was somewhat less so with... 

The relative stereochemistry of the newly formed stereogenic centers attained in the aminometa-lation reaction of 1,2-disubstituted alkenes is lost if the / -aminoalkylpalladium complex is allowed to undergo /J-hydride elimination to give enamines, or if a successive reduction step is performed, unless a stereocenter is initially present in the alkene or in the amine. However, the C —Pd bond can be functionalized to achieve overall oxyamination, diamination, aziridination, aminocarbonylation, and carboamination reactions13,14. 

Die aus 1,2-Oxazolen zuganglichen l-Amino-3-oxo-l-alkene (s. Bd. E8a, S. 185ff.) fiihren mit Hydrazinen bzw. Aminocarbonyl-hydrazin in guter Ausbeute zu lH-Pyrazolen... 

Mannich reaction Alkylation of enols by electrophilic iminium ions, giving f)-aminocarbonyl compounds. Markovnikov rule Regioselectivity in electrophilic addition to alkenes whereby an electrophile attacks... 

The potential of palladium-catalyzed aminochlorination reactions of alkenes dates back to their isolation as side products in aminocarbonylation reactions under copper(II)dichloride cocatalysis [47d]. These reactions were later developed further using copper(II) salts as co-oxidants or reoxidants, respectively, and concomitantly as halide sources. For example, Chemler showed that various aminohalogenation reactions proceed under palladium catalysis in the presence of potassium carbonate as base in moderate to excellent yields in the presence of an excess of the copper oxidant [80]. Both five- and six-membered rings 115 and 116 were formed under these conditions from allyl anilines 114 (Scheme 16.28). Among other examples... 

The palladium] 11)-catalyzed alkoxy/aminocarbonylation reactions of alkenes and alkynes bearing a tethered nucleophile, usually oxygen or nitrogen nucleophiles, give rise to heterocyclic compounds and follow the mechanisms shown in Scheme 13.43. 

Shinohara, T., Arai, M.A., Wakita, K., Aral, T. and Sasai, H. (2003) The first enantioselective intramolecular aminocarbonylation of alkenes promoted by Pd(ll)-spiro bis(isoxazoline) catalyst. Tetrahedron Letters, 44, 711-714. 

Cobalt has also been used for aminocarbonylation reactions, Chung showed that a heterogeneous cobalt on charcoal catalyst could form amides from readily available alkenes and amines. However harsh reactions conditions and high CO pressures (150 °C, 70 atm) were required. 

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