The reactions of fac-[MnBr(CO) 3 (NHC(CH 3 )pz ∗ -κ 2 N,N)] (pz ∗ =pz, dmpz; pzH=pyrazole; dmpzH=3,5-dimethylpyrazole) with wet AgBF 4 in a 1:1 ratio lead to the cationic pyrazolylamidino complexes fac-[Mn(OH 2 )(CO) 3 (NHC(CH 3 )pz ∗ -κ 2 N,N)]BF 4 . The aquo ligand is readily substituted by 2,6-xylylisocyanide (CNXyl) to give fac-[Mn(CNXyl)(CO) 3 (NHC(CH 3 )pz ∗ -κ 2 N,N)]BF 4 . The pyrazole complexes fac-[Mn(pz ∗ H)(CO) 3 (NHC(CH 3 )pz ∗ -κ 2 N,N)]BF 4 are obtained by treating fac-[MnBr(CO) 3 (NCMe) 2 ] with AgBF 4 and then with pyrazole (pzH or dmpzH), in a 1:1:2 ratio. A similar reaction using 1:1:1 ratio and AgClO 4 leads to the acetonitrile complexes fac-[Mn(NCMe)(CO) 3 (NHC(CH 3 )pz ∗ -κ 2 N,N)]ClO 4 . The X-ray structures of the complexes show moderate hydrogen bonds interactions between the N-bond hydrogen of the pyrazolylamidino ligand and the anion. In the aquo complex, one of the hydrogens of the coordinated water molecule is also involved in a hydrogen bond.