Co-crystallized bis(hexafluoroacetylacetonato)palladium(II) and 3-cyano-2,2,5,5-tetramethyl-2,5-dihydropyrrolyl-1-oxyl, C10H2F12O4Pd.2C9H13N2O

Abstract

[Li(CaHloO2)3] [Zr2ClaO(C4H4N)2(C lo H 15)2].C4H 1002 The CsMe 5 ring shows r:-coordination: the Z r - C lengths range from 2.49 (1) to 2.57 (2)A. The bond lengths and angles within the ligands themselves are normal (Bynum, Hunter, Rogers & Atwood, 1980). The two independent L i - O lengths, 2.09 (1) and 2.20 (3) A, have large e.s.d.'s associated with them due to the high thermal motion of the cation. However, the distances are long when compared to the L i - O lengths of 2.064(9) and 2 . 1 1 2 ( 4 ) A found for the five- coordinate Li in [Li(dme)2lBr (Rogers & Atwood, 1983, unpublished results). An uncoordinated dme molecule was found highly disordered about a crystallographic twofold axis. Refinement of the parameters of this moiety could not be carried out, and the non-hydrogen atoms were included with fixed contributions. The rather high R value resulted from this difficulty. We are grateful to the National Science Foundation for support of this work. References BYNUM, R. V., HUNTER, W. E., ROGERS, R. D. & ATWOOD, J. L. (1980). Inorg. Chem. 19, 2368-2374. BYNUM, R. V., ZHANG, H., HUNTER, W. E. & ATWOOD, J. L. (1984). Can. J. Chem. Submitted. CROMER, D. T. & LmERMAN, D. (1970). J. Chem. Phys. 53, CROMER, D. T. & WABER, J. T. (1965). Acta Cryst. 18, 104-109. FACHINETTI, G., FLORIAN1, C., CHIES1-VILLA, A. & GUASTINI, C. (1979),J. Am. Chem. Soc. 101, 1767-1775. HOLTON, J., LAPPERT, M. F., BALLARD, D. G. H., PEARCE, R., ATWOOD, J. L. & HUNTER, W. E. (1979). J. Chem. Soc. Dalton Trans. pp. 45-53. HUNTER, W. E., HRNC1R, D. C., BYNUM, R. V., PENTTILA, R. A. & ATWOOD, J. L. (1983). Organometallics, 2, 750-755. LAPPERT, M. F., RILEY, P. I., YARROW, P. I. W., ATWOOD, J. L., HUNTER, E. W. & ZAWOROTKO, M. J. (1981). J. Chem. Soc. Dalton Trans. pp. 814-821. PETERSEN, J. L. (1979). J. Organomet. Chem. 166, 179-192. SALDARRIAGA-MOLINA, C. H., CLEARFIELD, A. & BERNAL, I. (1974). Inorg. Chem. 13, 2880-2885. WOLCZANSKI, P. T., THRELKEL, R. S. & SANTARSlERO, B. D. (1983). Acta Co'st. C39, 1330-1333. Acta Cryst. (1984). C40, 1814-1817 Co-crystallized Bis(hexafluoroacetylacetonato)palladium(II) and 3-Cyano-2,2,5,5- tetramethyl-2,5-dihydropyrrolyl- l-oxyl, C 10H2F 12 O4Pd.2C9H13 N20 BY LEIGH C. PORTER AND ROBERT J. DOEDENS* Department o f Chemistry, University o f California, Irvine, California 92717, USA (Received 16 April 1984; accepted 28 June 1984) M r=850.9, monoclinic, P2x/n, a = b=19.139(7), c = 1 0 . 9 2 8 ( 3 ) A, f l = v = 1772 (1) A 3, z = 2, Dx= 1.595 Mg m -3, 2(Mo Ka) = 0.71073 A, g = 0.62 mm -l, F ( 0 0 0 ) = 8 5 2 , T = 2 9 6 K , final R = 0 . 0 4 5 for 2498 observed reflections. The co-crystallized species are arranged in alternating layers perpendicular to the b axis, with only van der Waals type interactions between layers. Magnetic susceptibility data (6-300 K) are consistent with the presence of one free spin on each nitroxyl radical. Abstract. I n t r o d u c t i o n . Several complexes in which a transition- metal ion is directly bound to a nitroxyl group have recently been prepared and characterized by crystal structure analyses (Anderson & Kuechler, 1980; Dickman & Doedens, 1983; Porter, Dickman & Doedens, 1983; Dickman, 1983). These molecules constitute a relatively rare example of a series of metal * To whom correspondence should be addressed. complexes containing a coordinated flee-radical ligand which retains its radical character. They also show other interesting features, including unusual metal- ligand binding geometries and various types of mag- netic behavior. One factor which favors formation of a metal-nitroxyl bond is a strongly Lewis acidic metal center. Most frequently this has been achieved by the presence of electron-withdrawing groups on other ligands. The nature of the nitroxyl ligand is also a factor, though this has not been thoroughly investigated. The title compound was prepared in the course of exploratory studies designed to define the conditions under which a transition-metal-nitroxyl bond will be formed. From bis(hexafluoroacetylacetonato)- palladium(II) [Pd(F6acac) 2] and 3-cyano-2,2,5,5-tetra- methyl-2,5-dihydropyrrolyl-1-oxyl (tmpCN) in pentane a compound of stoichiometry Pd(F6acac)2(tmpCN)2 was obtained in good yield. A crystal structure analysis was performed to establish the mode of binding of the tmpCN in this material. © 1984 International Union of Crystallography