Addition von kationischen Lewis‐Säuren [M′L n ] + (M′L n = Fe(CO) 2 Cp, Fe(CO)(PPh 3 )Cp, Ru(PPh 3 ) 2 Cp, Re(CO) 5 , ${1 \over 2}$ Pt(PPh 3 ) 2 , W(CO) 3 Cp an die anionischen Thiocarbonyl‐Komplexe [HB(pz) 3 (OC) 2 M(CS)] − (M = Mo, W; pz = 3,5‐dimethylpyrazol‐1‐yl)

Addition of Cationic Lewis Acids [M′L n ] + (M′L n = Fe(CO) 2 Cp, Fe(CO)(PPh 3 )Cp, Ru(PPh 3 ) 2 Cp, Re(CO) 5 , ${1 \over 2}$ Pt(PPh 3 ) 2 , W(CO) 3 Cp to the Anionic Thiocarbonyl Complexes [HB(pz) 3 (OC) 2 M(CS)] − (M = Mo, W; pz = 3,5‐dimethylpyrazol‐1‐yl) Adducts from Organometallic Lewis Acids [Fe(CO) 2 Cp] + , [Fe(CO)(PPh 3 )Cp] + , [Ru(PPh 3 ) 2 Cp] + , [Re(CO) 5 ] + , [ ${1 \over 2}$ Pt(PPh 3 ) 2 ] + , [W(CO) 3 Cp] + and the anionic thiocarbonyl complexes [HB(pz) 3 (OC) 2 M(CS)] − (M = Mo, W) have been prepared. Their spectroscopic data indicate that the addition of the cations occurs at the sulphur atom to give end‐to‐end thiocarbonyl bridged complexes [HB(pz) 3 (OC) 2 MCSM′L n ].