This work concerns the synthesis, spectroscopic analysis, and reactivity of tetracarbonyliron bis (dimethylgermy1) alkanes MezGe (CHz), Ge (Mez) Fe (C0) 4 (n= 1, 2). These heterocycles are obtained by cyclization of bis (dimethylgermy1) alkanes MezHGe (CHz), GeHMez (n= 1, 2) with Fe (C0) 5 under UV irradiation. They are stable at room temperature, but the heterocycle with n= 1 decomposes under prolonged UV irradiation with formation ...