The metal reduction of 1,3-diphenylbenzo[c]furan (1) t o the corresponding dianion (I2-) has been carried out by alkali-metals. A detailed (1 D and 2D) n.m.r. investigation of (12-) enables characterization of its charge distribution as well as its spatial structure. The spectra of (I2-) differs when three alkalimetals are used for the reduction process. These differences are explained by an ion-solvation equilibrium which in turn explains the different stereoselectivity observed in the

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... g experiments of the salts of (I2-). The reduction process induces in (I2-) a very high energy barrier for the rotation of the phenyl substituents.