He-3 NMR spectrometry has been used to examine bisaddition to C-60 containing an encapsulated He-3 atom (He-3@C-60) using three types of reactions : (1) cyclopropanation with diethyl bromomalonate and base to give dicarbethoxymethanofullerenes (Bingel-Hirsch reaction), (b) addition of azomethine ylides to give N-methyl-fulleropyrrolidines (Prato-Wudl reaction), and (c) reduction to give C60H4. He-3 NMR spectra of crude reaction mixtures in all three series showed well-separated resonances for each of the bisadducts, spread out over more than 2 ppm. The major isomeric bisadducts from the first two reactions were separated and characterized, and the He-3 NMR spectra of the individual major bisadducts from He-3@C-60 were obtained (five isomers from reaction 1, four isomers from reaction 2). Although the absolute chemical shifts in the two series of bisadducts differ, the relative chemical shifts are significantly but not perfectly correlated. Bisadducts with appended ligands on opposite hemispheres of C-60 (7, 6, and 5) tend to have He-3 NMR resonances downfield of the bisadducts with appended ligands on the same hemisphere (bisadducts 2 and 3). Unfortunately, the equatorial isomer 4, a major product from the Hirsch addition reaction, was not obtained in sufficient quantity for study from the Prate reaction. Well-separated resonances were also seen for the isomeric compounds of composition He-3@C60H4 from reaction of the fullerene with diimide, but the individual isomers were not separated. The very large differences in the He-3 NMR chemical shifts of the isomeric bisadducts in all three reactions demonstrate that the magnetic field felt by the He-3 atom due to the ring currents in the residual pi-system is extremely sensitive to the pattern of ligation on the C-60 surface. These results provide further support for the assertion that He-3 NMR is a very sensitive probe of patterns of chemical addition to fullerenes, and suggest that this technique will prove to be generally useful in determining the ratio as well as the identity of isomeric fullerene bisadducts.