MULTIPLE BONDS BETWEEN MAIN GROUP ELEMENTS AND TRANSITION-METALS .95. SYNTHESIS AND REACTIVITY OF TCCL(CO)3[P(C6H5)3]2 - NOVEL TECHNETIUM COMPLEXES OF 1,4,7-TRIAZACYCLONONANE AND HYDRIDOTRIS(PYRAZOLYL)BORATE

trans-TcCl(CO)3[P(C6H5)3]2 (2) is accessible in 95% yield by treatment of the easily available Tc(V) ionic precursor [TcOCl4]- (1) with triphenylphosphine in an atmosphere of carbon monoxide (1 atm). 2 is recognized as a useful starting material for subsequent substitution reactions, especially with tridentate nitrogen ligands. Thus, the compounds [(C6H15N3)Tc(CO)2{P(C6-H5)3}]Cl (5) and [HB(C3H3N2)3]Tc(CO)2{P(C6H5)3}] (6) were synthesized in good yields. The structures of compounds 2, 5, and 6 were determined by single-crystal X-ray diffraction techniques. 2 crystallizes in the triclinic space group P1BAR (No. 2) with a = 10.245 (1) angstrom, b = 12.744 (1) angstrom, c = 14.423 (1) angstrom, alpha = 69.42 (1)-degrees, beta = 74.89 (1)-degrees, gamma = 81.51 (1)-degrees, R = 0.029, and R(w) = 0.025. Compound 5 crystallizes in the monoclinic space group P2(1)/c (No. 14) with a = 12.997 (5) angstrom, b = 8.680 (1) angstrom, c = 25.189 (5) angstrom, beta = 101.13 (4)-degrees, R = 0.059, and R(w) = 0.037. Compound 6 crystallizes in the monoclinic space group C2/c (No. 15) with a = 31.191 (8) angstrom, b = 9.7252 (6) angstrom, c = 18.818 (5) angstrom, beta = 93.36 (1)-degrees, R = 0.045, and R(w) = 0.033.