Inorg. Chem. 1986, 25. 3690-3693
3690
bridging unit to design magnetic systems with expected magnetic teractions. Therefore, i t should be expected t o exhibit stronger properties. antiferromagnetic interactions mainly of intermolecular nature. Actually, this is t h e case of t h e dimer [ C U , ( K - T P H A ) ( ~ ~ ~ ) ~ - Registry No. 1, 103817-49-8; 2, 103817-51-2; 3, 103834-81-7; 4, (H20),] prepared by us,' which indeed showed stronger 103817-53-4; 5, 103817-55-6. magnetic interaction ( J -26 cm-'). Finally, it is worth noting Supplementary Material Available: Table I (analytical data), Table t h a t t h e magnetic exchange interactions, if any, of t h e I.c-tereI1 (extended Hiickel parameters), Tables IV-VI11 (variable-temperature phthalato dimers t h a t d o not possess suitable orbital pathways magnetic susceptibility data), and Figures 2 and 4 (temperature depenmust be mainly intermolecular. However, it seems clear that the dence of x M Tand 1 /xMfor 2 and 4) (1 5 pages). Ordering information is given on any current masthead page. terephthalato dianion, under certain conditions, is a n appropriate
Contribution from the Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322-0300
Metal Complexes Containing the Trimethylamine-Carboxylatoborane Ligand: Synthesis (M = Cr(III), Fe(II1); R = and Characterization of [M30((CH3)3N-BH2C02)6R3]+XH20, CH30H; X- = NO3-, C1-) Verrill M. Norwood, 111, and Karen W. Morse* Received October 18, 1985 The coordination chemistry of Cr(II1) and Fe(II1) with the trimethylamine-carboxylatoborane ligand [(CH,),N.BH2C02-] has been studied by using magnetic moments and infrared, proton and boron-I 1 NMR, and visible spectroscopies. The complexes have the formulation [M30((CH3)3N.BH2C02)6(R)3]tX(M = Cr(III), Fe(II1); R = H 2 0 , CH,OH; X- = NO
