[{CpFe(CO) 2 } 2 l-(NH 2 (CH 2 ) n NH 2 )](BF 4 ) 2 (n = 2-4) (3), respectively. These complexes have been fully characterized and the mass spectral patterns of complexes 2 are reported. The structures of compounds 2a (n = 2) and 2b (n = 3) have been confirmed by single crystal X-ray crystallography. The single crystal X-ray diffraction data show that complex 2a, [CpFe(CO) 2 NH 2 (CH 2 ) 2 CH 3 ]BF 4 , crystallizes in a triclinic P 1 space group while 2b, [CpFe(CO) 2 NH 2 (CH 2 ) 3 CH 3 ]BF 4 , crystallizes in an orthorhombic Pca2 1 space group with two crystallographically independent molecular cations in the asymmetric unit. Furthermore, the reaction of 1 with 1-alkenes gives the g 2 -alkene complexes in high yield.