Tetrahedron letters

Tandem Parham cyclisation––α-amidoalkylation reaction in the synthesis of the isoindolo [1, 2-a] isoquinoline skeleton of nuevamine-type alkaloids

I Osante, E Lete, N Sotomayor

Index: Osante, Inaki; Lete, Esther; Sotomayor, Nuria Tetrahedron Letters, 2004 , vol. 45, # 6 p. 1253 - 1256

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Citation Number: 47

Abstract

C-12b substituted isoindolo [1, 2-a] isoquinolones are prepared efficiently via a tandem Parham cyclisation––α-amidoalkylation reaction. Thus, Parham cyclisation on imide generates a 12b-hydroxy isoindolo [1, 2-a] isoquinolone, which is an immediate precursor of an N-acyliminium ion. Intermolecular alkylation with different π-nucleophiles (allyl silanes or enol ethers) is accomplished upon treatment with Lewis acids (BF3· OEt2, TiCl4) to obtain ...