We report the details of our study to synthesize a new endohedral fullerene, H-2@C-60, in more than 100 mg quantities by closure of the 13-membered ring orifice of an open-cage fullerene using fourstep organic reactions. The 13-membered ring orifice in a previously synthesized open-cage fullerene incorporating hydrogen in 100% yield was reduced to a 12-membered ring by extrusion of a sulfur atom at the rim of the orifice, and the ring was further reduced into an eight-membered ring by reductive coupling of two carbonyl groups also at the orifice. Final closure of the orifice was completed by a thermal reaction. Purification of H-2@C-60 was accomplished by recycle HPLC. A gradual downfield shift of the NMR signal for the encapsulated hydrogen observed upon reduction of the orifice size was interpreted based on the gauge-independent atomic orbital (GIAO) and the nucleus-independent chemical shift (NICS) calculations. The spectral as well as electrochemical examination of the properties of H-2@C-60 has shown that the electronic interaction between the encapsulated hydrogen and outer C-60 pi-system is quite small but becomes appreciable when the outer pi-system acquires more than three extra electrons. Four kinds of exohedral derivatives of H-2@C-60 were synthesized. The tendency in the shift of the NMR signal of the inner hydrogen was found to be quite similar to that observed for the He-3 NMR signal of the corresponding derivatives of He-3@C-60.