Highly Selective Construction of Medium-Sized Lactams by Palladium-Catalyzed Intramolecular Hydroaminocarbonylation of Aminoalkynes
摘要:
A novel palladium-catalyzed intramolecular hydro-aminocarbonylation of aminoalkynes has been developed. This direct and operationally simple protocol provides a rapid and reliable approach to a diverse array of valuable seven- and eight-membered lactams with high chemoselectivity and regioselectivity. The high selectivity might be attributed to rational tuning the electronic nature of the amine moiety and the palladium catalyst, which enabled this transformation to proceed in the absence of acidic or any other additives under fairly mild reaction conditions. This method paves the way for the synthesis of medium-sized lactams.
作者:Ulrich Kloeckner、Peter Finkbeiner、Boris J. Nachtsheim
DOI:10.1021/jo302676g
日期:2013.3.15
An iodocyclization reaction of o-alkynylphenyl carboxaldehydes is reported that is truly catalytic with respect to the electrophilic iodine source. With a combination of tetrabutylammonium iodide (TBAI), Oxone as non-nucleophilic and easy to handle co-oxidant, and fluorinated protic solvents, highly substituted 1-naphthalenones could be prepared in high yields of up to 91%.