A New Approach to Bis(arene)titanium(0) and ‐titanium(– I ) Complexes; Structure of Bis(arene)titanates(1–)

The reduction of titanium tetrachloride with arene radical anions (such as biphenyl or 4,4′‐di‐ tert ‐butylbiphenyl potassium), as summarized in Equation (a), affords the corresponding bis(arene)titanates(l—) K[ 1 ] and K[ 2 ] in high yields, which were structurally characterized as K[2.2.2]cryptand complexes. The oxidation of K[ 1 ] and K[ 2 ] with I 2 leads to the corresponding neutral bis(arene)titanium complexes. Such metallocenes were previously accessible only by metal atom–ligand cocondensation or sonochemical reactions.