The synthesis of 1-halonaphthalenes by the Cu-catalyzed benzannulation reaction of 2-(phenylethynyl)benzaldehyde and alkynes in the presence of the halogen reagents such as NBS, NCS, and NIS, was developed. This protocol afforded various type of 1-halonaphthalenes in moderate to excellent yields and the cross coupling reactions of 1-bromo-2-phenylnaphthalene prepared by this method with various reagents
The CuX2-mediated reaction of enynal units, including ortho-alkynylbenzaldehydes, with alkynes gives a variety of haloaromatic compounds stereoselectively in good to high yields. 2,2'-Binaphthyl skeletons are also readily prepared by the reaction of ortho-alkynylbenzaldehydes and diynes. The method was applied to the synthesis of poly-substituted tetracene derivatives (C) 2009 Elsevier Ltd. All rights reserved