The synthesis of the cyclopentadiene-fused dimethyldihydropyrene, CpDI-IP(H) 44, from DHP 31 was achieved in a seven-step synthesis in an overall yield of 7%. Deprotonation of 44 gave the Cp anion fused CpDHP anion 28. The photochromic properties of 28 were studied. It is found that 28 is photochromic and its behavior is intermediate between the parent DHP 31 and the benzannelated DHP 36. The 1H-NMR data of 28 were also analyzed and showed that the Cp anion has similar bond fixing effect on the DHP ring as benzene does, but to a lesser extent. The complexation of anion 28 to various metal centers has been investigated. While the reactions of 28 with Re(CO)5Br, (Cp*RuCl2)„ and FeC12 yielded (CpDHP)Re(CO)3 51. Cp*Ru(CpDHP) 52 and (CpDHP)2Fe 54 respectively, the reactions with Mn. Y. Yb(III) or Zr precursors either gave the starting materials back or resulted in the decomposition of 28 to unidentified products. Reaction of the protonated form CpDHP(H) 44 with Yb[N(SiMe3)2I(thf)2 afforded Yb(CpDHP)2(thf)2 57.