The synthesis of oxygenated naphthyl stannanes possessing ortho-methoxy substituents for use in stille coupling reactions

Article abstract of DOI:10.1071/C98106

The preparation of oxygenated naphthyl stannanes bearing an ortho-methoxy substituent is described, including stannanes (23) and (25) which are key intermediates for the synthesis of dimeric pyranonaphthoquinone antibiotics. Stannanes (17), (19) and (21)-(23) were obtained by metalhalogen exchange of the corresponding bromonaphthalenes. In an alternative approach to effect stannylation, a palladium(0)-mediated coupling reaction using hexaalkylditin reagents was examined. The Stille coupling reaction between naphthyl stannanes (23) and (25) and the corresponding bromonaphthalenes (11) and (24) failed to effect coupling to the desired binaphthyls.