Tetrahedron

Synthesis of naphthoquinone antibiotics by intramolecular alkyne cycloaddition to carbene-chromium complexes

MF Semmelhack, JJ Bozell, L Keller, T Sato, EJ Spiess…

Index: Semmelhack, M. F.; Bozell, Joseph J.; Keller, Leonard; Sato, Tadahisa; Spiess, E.J.; et al. Tetrahedron, 1985 , vol. 41, # 24 p. 5803 - 5812

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Citation Number: 87

Abstract

The reaction of carbene-chromium complexes with alkynes provides a direct route to naphthoquinone derivatives and is the key step in a new approach to the isochromanone antibiotics exemplified by deoxyfrenolicin (1) and nanaomycin A (2). While the regioselectivity of intermolecular addition of the appropriate unsymmetrical disubstituted alkyne is unfavourable, two successful approaches have been developed. Allylacetylene ...