Coordinatively and electronically unsaturated tris(trimethylsilyl)silyl complexes of manganese and iron

The neutral, bis(silyl) complexes M[Si(SiMe3)3]2(THF)n (3, M=Mn, n=2; 4, M=Fe, n=1) represent reactive, useful starting materials for the synthesis of various silyl derivatives of Mn and Fe. The reaction of 3 with dmpe (dmpe=Me2PCH2CH2PMe2) produced the yellow–orange complex Mn[Si(SiMe3)3]2(dmpe), which was characterized by X-ray crystallography as possessing MnSi distances of 2.643(4) and 2.642(3) Å. A related benzophenone complex, Mn[Si(SiMe3)3]2(OCPh2)2, is dark blue in color but possesses neutral ketone ligands (by IR spectroscopy and X-ray crystallography). The reaction of [NEt4]{Fe[Si(SiMe3)3]2Cl} with CO gave [NEt4]{Fe(CO)3[Si(SiMe3)3]2Cl}, and the reaction of 3 with CNXyl (Xyl=2,6-Me2C6H3) produced Mn[Si(SiMe3)3]2(CNXyl)(THF) and the reduced manganese complex (XylNC)5MnSi(SiMe3)3.