화학공학소재연구정보센터
Inorganic Chemistry, Vol.33, No.26, 6361-6368, 1994
Transition-Metal Complexes of Optically-Active Tris(Pyrazolyl)Hydroborates
The synthesis and characterization of a series of complexes of the recently reported (LeCloux, D. D.; Tokar, C. J.; Osawa, M.; Houser, R. P.; Keyes, M. C.; Tolman, W. B. Organometallics 1994, 13, 2855-2866) ligands tris(7(R)-isopropyl-4(R)-methyl-4,5,6,7-tetrahydroindazolyl)hydroborate (Tp(Menth)) and tris(7(S)-tert-butyl-4(R)-methyl-4,5,6,7-tetrahydroindazolyl)hydroborate (Tp(Mementh)) are presented. Specific complexes prepared are Tp(Menth)M(II)Cl (M(II) = Zn-II, Ni-II, Co-II, Cu-II, Mn-II, Fe-II), Tp(Mementh)Zn(II)Cl, Tp(Menth)M(II)(NO3) (M(II) = Cu-II, Ni-II), Tp(Menth)M(II)(OAc) (M(II) = Cu-II, Ni-II), Tp(Menth)Rh(I)(CO)(2), Tp(Menth)Ti(IV)Cl(3), and Tp(Menth)*(TiCl3)-Cl-IV, where Tp(Menth)* is an isomerized version of Tp(Menth) in which one pyrazolyl group is attached to boron via the more, rather than the less, hindered N atom. Structural hypotheses are proposed on the basis of analytical and spectroscopic data for all compounds and X-ray crystal structures for (TPZnCl)-Zn-Menth, Tp(Mementh)ZnCl, Tp(Menth)Ni(OAc), and Tp(Menth)*TiCl3. Pseudooctahedral 4-coordinate (Tp(Menth)MCl and Tp(Mementh)ZnCl), distorted square-pyramidal 5-coordinate [Tp(M)(Menth)- (OAc) and Tp(Menth)M(NO3)], and octahedral 6-coordinate (Tp(Menth)TiCl(3) and Tp(Menth)*TiCl3) metal ion geometries were identified. IR and NMR data indicated that Tp(Menth)Rh(CO)(2) exists as a mixture of 4- and 5-coordinate isomers. The combined synthetic, spectroscopic, and structural data for the complexes we have synthesized suggest that the chiral Tp ligands have effective steric properties similar to those of achiral variants with 3-tert-butyl or 3-isopropyl substituents on the pyrazolyl rings. X-ray data for Tp(Menth)ZnCl : orthorhombic, space group p2(1)2(1)2(1) (No. 19), at -101 degrees C, a = 9.658(7) Angstrom, b = 17.777(7) Angstrom, c = 20.058(6) Angstrom, V = 3444(5) Angstrom(3), Z = 4, R = 0.063 and R(W) = 0.049 for 4055 reflections with I > 2 sigma(I) and 379 parameters. X-ray data for Tp(Mementh)ZnCl : orthorhombic, space group P2(1)2(1)2(1) (NO. 19), at 24 degrees C, a = 11.170(4) Angstrom, b = 14.829(9) Angstrom, c = 23.063(9) Angstrom, V 3820(5) Angstrom(3), Z = 4, R = 0.055 and R(W) = 0.056 for 4566 reflections with I > 2 sigma(I) and 407 parameters. X-ray data for Tp(Menth)Ni(OAc) : orthorhombic space group P2(1)2(1)2(1) (No. 19), at 24 degrees C, a = 10.139(5), Angstrom, b = 18.248(8) Angstrom, c = 19.700(8) Angstrom, V = 3645(5) Angstrom(3), Z = 4, R = 0.043 and R(W) = 0.039 for 3721 reflections with I > 2 sigma(I) and 406 parameters. X-ray data for Tp(Menth)*TiCl3.CH2Cl2 : orthorhombic, space group P2(1)2(1)2(1) (No. 19), at -100 degrees C, a = 10.335(8) Angstrom, b = 15.430(7) Angstrom, c = 25.11(1) Angstrom, V = 4004(7) Angstrom(3), Z = 4, R = 0.070 and R(W) = 0.071 for 3831 reflections with I > 2 sigma(I) and 424 parameters.