A series of eta(2)-N-2-titanium aryldiazoalkane complexes Cp*Ti-2(N2CHAr) (5-10), where Ar is a parasubstituted aryl group, have been prepared by addition of aryldiazoalkanes to CP*Ti-2(C2H4) (4) Unlike most diazoalkane complexes, they release dinitrogen thermally to give transient carbene complexes which may be trapped with styrene to form the titanacyclobutane complexes Cp*Ti-2(CHArCHPhCH2) (11-15). The kinetics of these reactions in toluene-d(s) at 78.0 degrees C have been examined by H-1 NMR spectroscopy. A Hammett analysis (rho = - 0.26) indicated that the reaction is relatively insensitive to para-substituents on the aromatic ring of the diazoalkane ligand, but application of the E- and C-based dual parameter substituent constant analysis suggests that this may be due to almost exactly compensating covalent and electrostatic contributions of each substituent to the reaction rate. The stability of the aryldiazoalkane complexes at temperatures below 75 degrees C allows their reactivity to be explored without competitive Nz loss. The addition of (BuNC)-Bu-c results in a coordination change of the diazoalkane fragment from eta(2) to eta(1) to give Cp*Ti-2(eta(1)-N2CHPh)((BuNC)-Bu-t) (16), as shown by N-15 NMR chemical shifts and N-H coupling constants. The bound (BuNC)-Bu-t ligand exchanges with free (BuNC)-Bu-t in solution, as established by an EXSY experiment. Trineopentylaluminum coordinates to the terminal nitrogen atom on the diazoalkane fragment to form Cp*2TiN(AlNp3)N(C(H)C6H4Me) (17), as determined by X-ray crystallography. Silanes (HSiR3; R-3 = PhH2, Ph2H) add across the Ti-N bond of Cp*(2)-Ti(N2C(H)C6H4Me) to give (E)-Cp*Ti-2(H)(N(SiR3)(N=C(H)C6H4Me) ((E)-19, (E)-20), the kinetic product and (Z)-Cp*Ti-2(H)(N(SiR3)(N=C(H)C6H4Me) ((Z)-19, (2)-20), the thermodynamic product. Diazoalkane adduct Cp*Ti-2(N2C(H)C6H4Me) undergoes N-N bond cleavage when treated with CO to form an alkylideneimido isocyanato complex Cp*Ti-2(NCO)N=C(H)C6K4Me) (21).