Formation of a 1-Azaallenylidene Ligand by Reaction of an Amido Complex with Tetracyanoethylene Dolores Morales, † Julio Pe ´rez,* ,† Lucı ´a Riera, † Vı ´ctor Riera, † and Daniel Miguel ‡ Departamento de Quı ´mica Orga ´ nica e Inorga ´ nica/IUQOEM Facultad de Quı ´mica, UniVersidad de OViedo-CSIC, 33071, OViedo, Spain, and Departamento de Quı ´mica Inorga ´ nica, Facultad de Ciencias, UniVersidad de Valladolid, 44071 Valladolid, Spain Received April 23, 2002 Amido complexes of Mo(II) allyl carbonyl fragments containing monodentate amido ligands, prepared by reaction of suitable chloro precursors with potassium amides, react (for the N(H)(p-tolyl) derivative) with tetracyanoethylene to give a 1-azaallenylidene complex. The strong electrophile tetracyanoethylene (TCNE) reacts with organic amines undergoing the sequential replacement of two CN groups to afford 1,1-diamino-2,2-dicyanoethyl- enes. 1 The reactivity of TCNE toward N-metalated amines, i.e., amido complexes, has not been studied. Coordination compounds containing polycyanoethylene moieties, which could be envisaged as products, have attracted considerable attention. 2 Amido complexes may show an enhanced reactiv- ity compared with free amines as a result of π conflict between the nitrogen lone pair of the amido ligand and filled metal d orbitals. 3 However, in most stable amido compounds, this reactivity is mitigated by π donation from the amido nitrogen to empty d orbitals, by steric hindrance due to bulky ancillary ligands, or by both factors. 4 We recently found that the reaction of [MoCl(η 3 -allyl)- (CO) 2 (phen)] (phen ) 1,10-phenanthroline) complexes with NaOMe affords stable yet highly reactive alkoxo complexes, 5 and we thought that a similar route could be used to prepare amido derivatives. Here we report the synthesis and structure of new amido complexes [Mo(N(p-tolyl)R)(η 3 -C 3 H 4 -Me-2)- (CO) 2 (phen)] (R) H or p-tolyl) and their reactivity toward TCNE. The reactions of [MoCl(η 3 -C 3 H 4 -Me-2)(CO) 2 (phen)] (1) with K[NR(p-tol)] (R ) H or p-tolyl) afforded the amido complexes [Mo(N(p-tol)R)(η 3 -C 3 H 4 Me-2)(CO) 2 (phen)] 6 (R ) H, 2; p-tolyl, 3) (Scheme 1), which were characterized by IR and NMR spectroscopy and, for 3, by X-ray diffraction (Figure 1). 7 * Author to whom correspondence should be addressed. E-mail: japm@ sauron.quimica.uniovi.es. Fax: 0034985103446. † Universidad de Oviedo-CSIC. ‡ Universidad de Valladolid. (1) (a) Fatiadi, A. J. Synthesis 1986, 249. (b) Dhar, D. N. Chem. ReV. 1967, 67, 611. (c) Cairns, T. L.; McKusick, B. C. Angew. Chem. 1961, 73, 520. (2) (a) Hartmann, H.; Kaim, W.; Hartenbach, I.; Schleid, T.; Wanner, M.; Fiedler, J. Angew. Chem., Int. Ed. 2001, 40, 2842. (b) Nemykin, V. N.; Kobayashi, N. Chem. Commun. 2001, 165. (c) Gordon, D. C.; Deakin, L.; Arif, A. M.; Miller, J. S. J. Am. Chem. Soc. 2000, 122, 290. (d) Pokhodnya, K. I.; Epstein, A. J.; Miller, J. S. AdV. Mater. 2000, 12, 410. (e) Hoshino, H.; Iida, K.; Kawamoto, T.; Mori, T. Inorg. Chem. 1999, 38, 4229. (3) (a) Jayaprakash, K. N.; Gillepsie, A. M.; Gunnoe, T. B.; White, D. P. Chem. Commun. 2002, 372. (b) Caulton, K. G. New J. Chem. 1994, 18, 25. (c) Mayer, J. M. Comments Inorg. Chem. 1988, 8, 125. (4) (a) Mindiola, D. J.; Hillhouse, G. L. J. Am. Chem. Soc. 2001, 123, 4623. (b) Jayaprakash, K. N.; Conner, D.; Gunnoe, T. B. Organome- tallics 2001, 20, 5254. (c) Flood, T. C.; Lim, J. K.; Deming, M. A.; Keung, W. Organometallics 2000, 19, 1166. (d) Cummins, C. C. Chem. Commun. 1998, 1777. (e) Gunnoe, T. B.; White, P. S.; Templeton, J. L. J. Am. Chem. Soc. 1996, 118, 6916. (f) Francisco, L. W.; White, P. S.; Templeton, J. L. Organometallics 1996, 15, 5127. (5) Hevia, E.; Pe ´rez, J.; Riera, L.; Riera, V.; Miguel, D. Organometallics 2002, 21, 1750. (6) Synthesis of 2: K[N(H)(p-tol)] (0.26 mmol) in THF (10 mL) was added to a solution of 1 (100 mg, 0.24 mmol) in THF (10 mL) at -78 °C. After stirring for 10 min, in vacuo solvent evaporation, extraction of the residue (CH 2Cl2,2 × 5 mL), filtration (Celite), in vacuo concentration to 5 mL, layering with hexane (20 mL), and standing at -20 °C, red crystals were obtained. Yield: 107 mg, 92%. Anal. Calcd for C 25H23MoN3O2: C, 60.86; H, 4.70; N, 8.52. Found: C, 60.71; H, 4.97; N, 8.55. IR (νCO) (CH2Cl2): 1926, 1839. 1 H NMR (CD2Cl2): 8.94 [dd (JH2,3 ) JH9,8 ) 5.0, JH2,4 ) JH7,9 ) 1.3), 2H, H2,9], 8.45 [dd (JH4,3 ) JH7,8 ) 8.6 Hz), 2H, H4,7], 7.99 [s, 2H, H5,6], 7.76 [dd, 2H, H3,8], 6.69, 6.66, 6.60 and 6.57 [AA′BB′, 4H, C6H4], 3.90 [s br, 1H, N-H], 3.00 [s, 2H, Hs], 2.08 [s, 3H, C6H4-CH3], 1.48 [s, 2H, Ha], 0.64 [s, 3H, η 3 -C3H4(CH3)-2]. 13 C{ 1 H} NMR (CD2- Cl2): 231.4 [CO], 158.8, 151.7, 144.5, 137.4, 130.6, 129.4, 127.7, 125.3, 121.7 and 115.8 [phen and C6H4], 87.8 [C 2 , η 3 -C3H4(CH3)], 68.1 [C 1 and C 3 , η 3 -C3H4(CH3)-2], 26.0 [C6H4-CH3], 20.1 [η 3 -C3H4- (CH3)-2]. (7) Crystal data for 3:C32H29MoN3O2, M ) 583.52, monoclinic, space group P21/n, a ) 13.194(4) Å, b ) 12.113(3) Å, c ) 17.992(5) Å,  ) 105.471(4)°, V ) 2771.1(13) Å 3 , T ) 293 K, Z ) 4, Dcalcd ) 1.399 Mg/m 3 , F(000) ) 1200, µ(Mo KR) ) 0.507 mm -1 , reflections collected/unique ) 11944/3978 (Rint ) 0.0828); parameters, 346; final R1 ) 0.0789, wR2 ) 0.1178 (all data), GOF) 1.010, max/min residual electron density 0.698/-0.715 e Å -3 , solution and refinement using SHELXL. 20 Scheme 1 Inorg. Chem. 2002, 41, 4111-4113 10.1021/ic025665b CCC: $22.00 © 2002 American Chemical Society Inorganic Chemistry, Vol. 41, No. 16, 2002 4111 Published on Web 07/13/2002