Iron By R. Davis 1 Manganese

There have been several publications reporting cationic manganese carbonyl complexes and a number of new synthetic routes to complexes of this type have been developed. The most unusual of these is  

Brunner has continued his studies on optically active manganese carbonyl complexes and has reported that treatment of Mn(CO)5Br with ort/to-Me2NC6H4PPh2 (PN) yields two enantiomers of/ac-[Mn(CO)3(PN)Br], Treatment of this complex with carbon monoxide in the presence of A1C13 produces the cation [Mn(CO)4(PN)] +, which was isolated as its hexafluorophosphated salt. Addition of menthoxide anions to the manganese carbonyl cation yields the diastereoisomers of Mn(CO)3(PN) (CO2C30H 9) however, these could not be separated due to their instability. Reaction of Mn(CO)5Br with the Schiff base NN (1) leads to formation of two isomers of 

Mn(CO)3(NN )Br, with different configurations at the metal atom. The diastereoisomers exhibit different n.m.r. spectra and can be obtained in optically active forms.14 Direct reaction of [(ft5-MeCp)Mn(CO)2(NO)]PF6 with Ph2PNMeCHMePh (L) yields diastereoisomeric pair, [(/i5-MeCp)Mn(CO)(NO)L]PF6, which are also 

Brunner and W. Rambold, Angew. Client. Intermit. Edit.. 1973. 12. 1013. 

Indium or gallium metal reacts with either Mn2(CO)10, Hg[Mn(CO)5]2, or mercury and Mn2(CO)10 to form M2Mn4(CO)18 (M = In or Ga). The indium compound can also be prepared by thermolysis of In[Mn(CO)5]3 and an X-ray study showed it to have structure (2) in which the Mn(CO)5 units are trans with respect to 

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