 The compound was first prepared in low yield by the reduction of manganese iodide with magnesium under CO. A more efficient preparation entails reduction of anhydrous MnCl2 with sodium benzophenone ketyl under 200 atmospheres of CO.The availability of inexpensive methylcyclopentadienyl manganese tricarbonyl ("MMT") has led to a low pressure route to Mn2(CO)10.Mn2(CO)10 has no bridging CO ligands