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Porphyrin Carbene Complexes: (5,10,15,20-Tetra-P-Tolylporphyrinato )

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Porphyrin Carbene Complexes: (5,10,15,20-Tetra-P-Tolylporphyrinato ) Chemistry Publications Chemistry 8-1994 Properties and Molecular Structures of Osmium(ll) Porphyrin Carbene Complexes: (5,10,15,20-Tetra-p-tolylporphyrinato )osmium Di-p-tolylmethylidene and (5,10,15,20-Tetra-p- tolylporphyrinato)osmium (Trimethylsilyl)methylidene Jean-Pierre Djukic Iowa State University Daniel A. Smith Iowa State University Victor G. Young Jr. Iowa State University Follow this and additional works at: http://lib.dr.iastate.edu/chem_pubs L. Keith Woo IowaP Satrate of U ntheiversitCyhe, kmiwoo@istryas Ctaommonte.edu s The ompc lete bibliographic information for this item can be found at http://lib.dr.iastate.edu/ chem_pubs/727. For information on how to cite this item, please visit http://lib.dr.iastate.edu/ howtocite.html. This Article is brought to you for free and open access by the Chemistry at Iowa State University Digital Repository. It has been accepted for inclusion in Chemistry Publications by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Properties and Molecular Structures of Osmium(ll) Porphyrin Carbene Complexes: (5,10,15,20-Tetra-p-tolylporphyrinato )osmium Di-p- tolylmethylidene and (5,10,15,20-Tetra-p-tolylporphyrinato)osmium (Trimethylsilyl)methylidene Abstract The first molecular structures of two (porphyrinato)osmium(II) alkylidene complexes are described. The carbene fragments of (5,10,15,20-tetra-p-tolylporphyrinato)osmium (trimethylsilyl) methylidene (1) and (5,10,15,20-tetra-p-tolylporphyrinato)osmium di-p-tolylmethylidene (2) adopt different conformations in the solid state. With respect to the porphyrin ring nitrogen atoms, a staggered conformation is found for the complex 1 carbene moiety (dos-e = 1. 79(2) A, torsion angle ¢ = 23(1)0 ). A similar conformation appears in complex 2 (dos-e= 1.865(5) A, torsion angle¢= 28.4(4)0 ). The carbene fragments in the two molecular structures are distorted and do not possess ideal sp2 geometries. Complex 1 displays a large distortion with an Os-C-Si angle of 142(2)0 • The ompc lex 2 carbene moiety has a CAr-C-CAr angle of 113.0(4)0 • Complex 1, C52H46N40sSioOCJia, crystallizes with a transcoordinated molecule ofTHF as 1·111F in the monoclinic space group P21/n with a = 13.954- (2) A, b = 9.522(2) A, c = 17.969(2) A, f3 = 101.42(1)0 , v = 2340.3(6) A3, z = 2, Rl = 0.0532, and wR2 = 0.1276. Complex 2, CsaH5oN40soOC4HaoC7Ha·1/20CJia, crystallizes as a transTHF adduct, 2·THF, in the monoclinic space group C2/c with a = 28.003(6) A, b = 14.385(3) A, c = 33.748(8) A, f3 = 114.51(2)0 , V = 12370(5) A3, Z = 8, Rl = 0.0389, and wR2 = 0.1165. Other metrical parameters and spectroscopic properties of these complexes are discussed. Disciplines Chemistry Comments Reprinted (adapted) with permission from Organometallics 13 (1994): 3020, doi:10.1021/om00020a018. Copyright 1994 American Chemical Society. This article is available at Iowa State University Digital Repository: http://lib.dr.iastate.edu/chem_pubs/727 3020 Organometallics 1994, 13, 3020-3026 Properties and Molecular Structures of Osmium(ll) Porphyrin Carbene Complexes: (5,10,15,20-Tetra-p-tolylporphyrinato )osmium Di-p-tolylmethylidene and (5,10,15,20-Tetra-p-tolylporphyrinato)osmium (Trimethylsilyl)methylidene Jean-Pierre Djukic, Daniel A. Smith, Victor G. Young, Jr., and L. Keith Woo*·1 Department of Chemistry, Gilman Hall, Iowa State University, Ames, Iowa 50011-3111 Received April 6, 1994161 The first molecular structures of two (porphyrinato)osmium(II) alkylidene complexes are described. The carbene fragments of (5,10,15,20-tetra-p-tolylporphyrinato)osmium (trim­ ethylsilyl)methylidene (1) and (5,10,15,20-tetra-p-tolylporphyrinato)osmium di-p-tolylmeth­ ylidene (2) adopt different conformations in the solid state. With respect to the porphyrin ring nitrogen atoms, a staggered conformation is found for the complex 1 carbene moiety 0 (dos-e = 1. 79(2) A, torsion angle ¢ = 23(1) ). A similar conformation appears in complex 2 0 (dos-e= 1.865(5) A, torsion angle¢= 28.4(4) ). The carbene fragments in the two molecular structures are distorted and do not possess ideal sp2 geometries. Complex 1 displays a large 0 distortion with an Os-C-Si angle of 142(2) • The complex 2 carbene moiety has a 0 CAr-C-CAr angle of 113.0(4) • Complex 1, C52H46N40sSioOCJia, crystallizes with a trans­ coordinated molecule ofTHF as 1·111F in the monoclinic space group P21/n with a = 13.954- 0 3 (2) A, b = 9.522(2) A, c = 17.969(2) A, f3 = 101.42(1) , v = 2340.3(6) A , z = 2, Rl = 0.0532, and wR2 = 0.1276. Complex 2, CsaH5oN40soOC4HaoC7Ha·1/20CJia, crystallizes as a trans­ THF adduct, 2·THF, in the monoclinic space group C2/c with a = 28.003(6) A, b = 14.385(3) 0 3 A, c = 33.748(8) A, f3 = 114.51(2) , V = 12370(5) A , Z = 8, Rl = 0.0389, and wR2 = 0.1165. Other metrical parameters and spectroscopic properties of these complexes are discussed. Introduction catalytic reactions mediated by osmium porphyrin complexes and may provide important information with We recently reported that (meso-tetra-p-tolylporphy­ regard to both mechanistic and reactivity aspects. rinato)osmium complexes such as Os2CTTP)2, Os(TTP)­ 6 (py)2, and Os(TTP)(C0)(py)2 are able to catalyze C-C Previous investigations of cyclopropanation reactions catalyzed by rhodium(III) metalloporphyrin complexes bond-forming reactions in the stereoselective formation 3 provided spectroscopic information on some of the of olefins by the condensation of diazoalkanes a and the 6 3 reaction intermediates. b,c However, none of the key cyclopropanation of alkenes with diazoalkanes. b Os­ rhodium porphyrin carbene species have been fully mium-carbene species, (TTP)Os=CRR', may be impor­ characterized structurally because of their very tran­ tant intermediates in these reactions, and several have sient nature. We report herein the first X-ray structural been isolated and characterized analytically and spec­ characterizations of two osmium porphyrin carbene troscopically. The Os porphyrin carbene complexes are complexes, trans-(TTP)Os=CHSiMea•THF ( 1•THF) and efficient catalysts for cyclopropanation. Moreover, these trans-(TTP)Os=C(p-CHa-CsH4)2·THF (2·THF). complexes are also active in the stoichiometric cyclo­ propanation of alkenes (Scheme 1). Results and Discussion Although a series of (porphyrinato)metal carbene complexes have been isolated4 in past years, only two Preparation of trans-(Tl'P)Os=CHSiMes·THF have been characterized by single-crystal X-ray diffrac­ (l•THF) and trans-(Tl'P)Os=C(Call4-p-Clls)2•THF tion analysis.5 Molecular structures of osmium porphy­ (4) (a) Mansuy, D.; Lange, M.; Chottard, J.-C.; Guerin, P.; Morliere, rin carbene complexes are relevant to our study of P.; Brault, D.; Rougee, M. J. Chem. Soc., Chem. Commun. 1977, 648. (b) Mansuy, D. Pure Appl. Chem. 1980, 52, 681. (c) Battioni, J.-P.; ®Abstract published in Advance ACS Abstracts, June 15, 1994. Dupre, D.; Guerin, P.; Mansuy, D. J. Organomet. Chem. 1984, 265, (1) Presidential Young Investigator, 1990-1995; Camille and Henry 53. (d) Artaud, I.; Gregoire, N.; Battioni, J.-P.; Dupre, D.; Mansuy, D. Dreyfus Teacher-Scholar, 1993-1998. J. Am. Chem. Soc. 1988, 110, 8714. (e) Collman, J. P.; Brothers, P. (2) Collman, J. P.; Barnes, C. E.; Woo, L. K. Proc. Natl. Acad. Sci. J.; McElwee-White, L.; Rose, E.; Wright, L. J. J. Am. Chem. Soc. 1985, U.S A. 1983, 80, 7684. List of abbreviations for ligand names: TTP, 107, 4570. (f) Collman, J.P.; Brothers, P. J.; McElwee-White, L.; Rose, 5,10,15,20-tetra-p-tolylporphyrinato; TPP, 5,10,15,20-tetraphenylpor­ E. J. Am. Chem. Soc. 1985, 107, 6110. (g) Jones, T. K.; McPherson, phyrinato; THF, tetrahydrofuran; py, pyridine. IUPAC. In Nomen­ C.; Chen, H.-L.; Kendrick, M. J. Inorg. Chem. Acta 1993, 206, 5. clature of Inorganic Chemistry; Leigh, G. J., Ed.; Blackwell Scientific: (5) (a) Mansuy, D.; Lange, M.; Chottard, J.-C.; Bartoli, J. F.; Oxford, U.K., 1991. Chevrier, B.; Weiss, R. Angew. Chem., Int. Ed. Engl. 1978, 17, 781. (3) (a) Woo, L. K.; Smith, D. A. Organometallics 1992, 11, 2344. (b) (b) Boschi, T.; Licoccia, S.; Paolesse, R.; Tagliatesta, P.; Pelizzi, G.; Smith, D. A.; Reynolds, D. N.; Woo, L. K. J. Am. Chem. Soc. 1993, Vitali, F. Organometallics 1989, 8, 330. 115, 2511. (c) A stereoselective alkene formation reaction has been (6) (a) Callot, H. J.; Metz, F.; Piechocki, C. Tetrahedron 1982, 38, published recently for a series of ruthenium(Il) porphyrin catalysts: 2365. (b) Maxwell, J. L.; Brown, K. C.; Bartley, D. W.; Kodadek, T. Collman, J.P.; Rose, E.; Venburg, G. D. J. Chem. Soc., Chem. Commun. Science 1992, 256, 1544. (c) Bartley, D. W.; Kodadek, T. J. Am. Chem. 1993, 934. Soc. 1993, 115, 1656. 0276-7333/94/2313-3020$04.50/0 © 1994 American Chemical Society Osmium([!) Porphyrin Carbene Complexes Organometallics, Vol. 13, No. 8, 1994 3021 Table 1. Crystallographic Data 1 2 empirical formula Cs2~40sSiOC.Jis C63HsoN40s<>C.JisoC,Hs•1/20C.Jis cryst size (mm) 0.44 x 0.18 x 0.09 0.35 x 0.35 x 0.12 cryst syst monoclinic monoclinic space group ntln C21c a (A) 13.954(2) 28.003(6) b (A) 9.522(2) 14.385(3) c <A) 17.969(2) 33.748(8) p (deg) 101.42(1) 114.51(2) v (A3) 2340.3(6) 12370(5) z 2 8 fw 1017.32 1253.53 density (calcd) (Mglm3) 1.444 1.345 ll (mm-1) 5.729 4.270 diffractometer Siemens P4/RA Siemens P4/RA radiation Cu Ku (A= 1.541 78 A) Cu Ku (A= 1.541 78 A) temp (K) 213(1) 223(1) monochromator graphite graphite 29range(deg) 5.0-115.0 5.0-115.0 scan type 29-e 29-e no.
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