Reactivity of a Bipyridyl Tantalum Complex toward Nitriles, Iso(thio)cyanates and Carbodiimides

doi:10.6023/A26070231

Abstract

Complexes of main group metals, lanthanides and actinides bearing reduced bipy ligand have garnered considerable attention and demonstrated notable potential in small-molecule activation. Nevertheless, the detailed reactivity studies on 2,2'-bipyridine-derived tantalum complexes remain largely unexplored. In this work, the divergent reactivity of a direduced bipyridyl tantalum complex (2,6-ⁱPr₂C₆H₃O)₃Ta(bipy) (1) toward small molecules bearing highly unsaturated functional groups is explored. For instance, when treatment of complex 1 with 1.0 equiv. of benzonitrile (PhCN) at room temperature, the C≡N bond in PhCN can insert into the bipy moiety of complex 1 through the reduction of C≡N bond followed by C—C coupling occurring at C6 or C6' of bipy in 1 and 1,5-H migration, forming the imido complex (2,6-ⁱPr₂C₆H₃O)₃Ta-(=NCHPh)(C₁₀H₇N₂) (2), which can further undergo 1,5-H migration at 100 ℃ to yield the bis-amido complex (2,6-ⁱPr₂C₆H₃O)₃Ta(N₂C₁₀H₇C(Ph)NH) (3). The aliphatic nitriles, including p-tolylacetonitrile (p-MeC₆H₄CH₂CN), acetonitrile (MeCN), cyclohexanecarbonitrile (CyCN) and pivalonitrile (^tBuCN) with primary, secondary, tertiary and quaternary carbons at the α-position of cyano group, respectively, react with 1 to form the analogous imido products (2,6-ⁱPr₂C₆H₃O)₃Ta(=NCH(R))(C₁₀H₇N₂) (R=p-MeC₆H₄CH₂ (4), Me (5), Cy (6) and ^tBu (7)). Among which, complexes 4-6 can also transform via 1,5-H migration into bis-amido complexes (2,6-ⁱPr₂C₆H₃O)₃Ta(N₂C₁₀H₇C(p-MeC₆H₄CH₂)NH) (8), (2,6-ⁱPr₂C₆H₃O)₃Ta(N₂C₁₀H₇C(Me)NH) (9) and (2,6-ⁱPr₂C₆H₃O)₃Ta(N₂C₁₀H₇C(Cy)NH) (10), respectively, whereas, complex 7 remains inert even when its toluene solution was heated at 120 ℃ for one week. Furthermore, phenyl isothiocyanate (PhNCS) and alkyl isocyanates (CyNCO and ^tBuNCO) can regioselectively couple with C2 or C2' of bipy moiety in 1 to form the insertion products (2,6-ⁱPr₂C₆H₃O)₃Ta(bipy)(PhNCS) (11), (2,6-ⁱPr₂C₆H₃O)₃Ta(bipy)(CyNCO) (12), and (2,6-ⁱPr₂C₆H₃O)₃Ta(bipy)(^tBuNCO) (13), respectively. During this process, the C=S and C=O bonds in iso(thio)cyanates are reduced, whereas the N=C double bonds remain intact, as confirmed by X-ray diffraction analysis. Conversely, 1 acts as a low valent Ta(III) synthon for (2,6-ⁱPr₂C₆H₃O)₃Ta(III)(bipy) when reacted with organic carbodiimides (RN=C=NR) (R=Ph, ⁱPr and Cy), yielding the neutral bipy coordinated tantalum imido complexes (2,6-ⁱPr₂C₆H₃O)₃Ta(=NR)(bipy⁰) (R=Ph (14), ⁱPr (15) and Cy (16)) via two-electron redox process.

Key words: reactivity, organotantalum, bipyridyl complex, small molecule activation, synthesis

Cite this article

Lei Zhang, Ping Zhang, Yanfeng Zhang. Reactivity of a Bipyridyl Tantalum Complex toward Nitriles, Iso(thio)cyanates and Carbodiimides[J]. Acta Chimica Sinica, 2026, 84(10): 1641-1648.

Export EndNote|Reference Manager|ProCite|BibTeX|RefWorks

share this article

Fig. & Tab. 6

Scheme 1. Syntheses of complexes 2~10

Figure 1. Molecular structures of 2 (top) and 3 (bottom) (thermal ellipsoids drawn at the 30% probability level, 2,6-iPr2C6H3 moieties attached to O atoms drawn in a wireframe for clarity). Selected bond lengths (nm): 2, Ta—N(1) 0.2386(4), Ta—N(2) 0.2265(4), Ta—N(3) 0.1798(4), C(41)—C(42) 0.1471(9), C(46)—C(47) 0.1517(8), N(3)—C(47) 0.1464(7); 3, Ta—N(1) 0.2254(2), Ta—N(2) 0.2140(2), Ta—N(3) 0.1996(2), C(41)—C(42) 0.1455(5), C(46)—C(47) 0.1359(4), N(3)—C(47) 0.1396(4)

Scheme 2. Syntheses of complexes 11~13

Figure 2. Molecular structures of 11 (top) and 12 (bottom) (thermal ellipsoids drawn at the 30% probability level, 2,6-iPr2C6H3 moieties attached to O atoms drawn in a wireframe for clarity). Selected bond lengths (nm): 11, Ta—N(1) 0.2283(5), Ta—N(2) 0.2062(5), Ta—S(1) 0.25215(17), C(41)—C(42) 0.1525(11), C(42)—C(47) 0.1564(11), N(3)—C(47) 0.1276(9), C(47)—S(1) 0.1744(8); 12, Ta—N(1) 0.2316(2), Ta—N(2) 0.2065(2), Ta—O(4) 0.20093(15), C(41)—C(42) 0.1536(4), C(42)—C(47) 0.1536(3), N(3)—C(47) 0.1258(3), C(47)—O(4) 0.1338(3)

Scheme 3. Syntheses of complexes 14~16

Figure 3. Molecular structures of 15 (top) and 16 (bottom) (thermal ellipsoids drawn at the 30% probability level, 2,6-iPr2C6H3 moieties attached to O atoms drawn in a wireframe for clarity). Selected bond lengths (nm) and angles (deg): 15, Ta—N(1) 0.24290(19), Ta—N(2) 0.23117(19), Ta—N(3) 0.1777(2), C(41)—C(42) 0.1479(4), Ta(1)—N(3)—C(47) 171.11(18); 16, Ta—N(1) 0.24219(18), Ta—N(2) 0.23032(17), Ta—N(3) 0.17773(18), C(41)—C(42) 0.1479(3), Ta(1)—N(3)—C(47) 176.20(15)

References 26

[1]	(a) Gibson, V. C.; Spitzmesser, S. K. Chem. Rev. 2003, 103, 283.
	(b) Sueyoshi, S.; Taniguchi, T.; Tanaka, S.; Asakawa, H.; Nishimura, T.; Maeda, K. J. Am. Chem. Soc. 2021, 143, 16136.
[2]	(a) Zi, G.; Zhang, F.; Song, H. Chem. Commun. 2010, 46, 6296.
	(b) DiPucchio, R. C.; Rosca, S.-C.; Schafer, L. L. J. Am. Chem. Soc. 2022, 144, 11459.
	(c) Ataie, S.; Schafer, L. L. Acc. Chem. Res. 2025, 58, 2956.
[3]	(a) Chirik, P. J. Inorg. Chem. 2011, 50, 9737.
	(b) Ma, W.; Yu, C.; Chi, Y.; Chen, T.; Wang, L.; Yin, J.; Wei, B.; Xu, L.; Zhang, W.-X.; Xi, Z. Chem. Sci. 2017, 8, 6852.
	(c) Lv, Z.-J.; Huang, Z.; Shen, J.; Zhang, W.-X.; Xi, Z. J. Am. Chem. Soc. 2019, 141, 20547.
[4]	(a) Munhá R. F.; Zarkesh, R. A.; Heyduk, A. F. Dalton Trans. 2013, 42, 3751.
	(b) Hananouchi, S.; Krull, B. T.; Ziller, J. W.; Furche, F.; Heyduk, A. F. Dalton Trans. 2014, 43, 17991.
	(c) O’Reilly, M. E.; Veige, A. S. Chem. Soc. Rev. 2014, 43, 6325.
[5]	(a) Zarkesh, R. A.; Ziller, J. W.; Heyduk, A. F. Angew. Chem., Int. Ed. 2008, 47, 4715.
	(b) Zarkesh, R. A.; Heyduk, A. F. Organometallics 2011, 30, 4890.
[6]	(a) Nguyen, A. I.; Blackmore, K. J.; Carter, S. M.; Zarkesh, R. A.; Heyduk, A. F. J. Am. Chem. Soc. 2009, 131, 3307.
	(b) Heyduk, A. F.; Zarkesh, R. A.; Nguyen, A. I. Inorg. Chem. 2011, 50, 9849.
	(c) Munhá R. F.; Zarkesh, R. A.; Heyduk, A. F. Inorg. Chem. 2013, 52, 11244.
[7]	(a) Tsurugi, H.; Saito, T.; Tanahashi, H.; Arnold, J.; Mashima, K. J. Am. Chem. Soc. 2011, 133, 18673.
	(b) Nishiyama, H.; Ikeda, H.; Saito, T.; Kriegel, B.; Tsurugi, H.; Arnold, J.; Mashima, K. J. Am. Chem. Soc. 2017, 139, 6494.
	(c) Parker, B. F.; Hosoya, H.; Arnold, J.; Tsurugi, H.; Mashima, K. Inorg. Chem. 2019, 58, 12825.
	(d) Nishiyama, H.; Hosoya, H.; Parker, B. F.; Arnold, J.; Tsurugi, H.; Mashima, K. Chem. Commun. 2019, 55, 7247.
	(e) Mashima, K. Bull. Chem. Soc. Jpn. 2020, 93, 799.
	(f) Fomenko, I. S.; Gushchin, A. L. Russ. Chem. Rev. 2020, 89, 966.
[8]	(a) Scarborough, C. C.; Wieghardt, K. Inorg. Chem. 2011, 50, 9773.
	(b) Li, B.; Geoghegan, B. L.; Wölper, C.; Cutsail, G. E., III; Schulz, S. ACS Omega 2021, 6, 18325.
[9]	(a) Gore-Randall, E.; Irwin, M.; Denning, M. S.; Goicoechea, J. M. Inorg. Chem. 2009, 48, 8304.
	(b) Gray, P. A.; Krause, K. D.; Burford, N.; Patrick, B. O. Dalton Trans. 2017, 46, 8363.
	(c) Ren, W.; Fang, X.; Sun, W.; Gu, D.; Yu, Y. J. Organomet. Chem. 2017, 842, 47.
	(d) Wu, L.; Wang, Z.; Liu, Y.; Chen, L.; Ren, W. Dalton Trans. 2023, 52, 7175.
	(e) Gong, X.; Shi, X.; Deng, P.; Cheng, J. Inorg. Chem. 2024, 63, 20654.
[10]	(a) Roitershtein, D.; Domingos, Â.; Pereira, L. C. J.; Ascenso, J. R.; Marques, N. Inorg. Chem. 2003, 42, 7666.
	(b) Carlson, C. N.; Kuehl, C. J.; Ogallo, L.; Shultz, D. A.; Thompson, J. D.; Kirk, M. L.; Martin, R. L.; John, K. D.; Morris, D. E. Organometallics 2007, 26, 4234.
	(c) Williams, B. N.; Huang, W.; Miller, K. L.; Diaconescu, P. L. Inorg. Chem. 2010, 49, 11493.
	(d) Booth, C. H.; Kazhdan, D.; Werkema, E. L.; Walter, M. D.; Lukens, W. W.; Bauer, E. D.; Hu, Y.-J.; Maron, L.; Eisenstein, O.; Head-Gordon, M.; Andersen, R. A. J. Am. Chem. Soc. 2010, 132, 17537.
	(e) Ortu, F.; Liu, J.; Burton, M.; Fowler, J. M.; Formanuik, A.; Boulon, M.-E.; Chilton, N. F.; Mills, D. P. Inorg. Chem. 2017, 56, 2496.
	(f) Fedushkin, I. L.; Yambulatov, D. S.; Skatova, A. A.; Baranov, E. V.; Demeshko, S.; Bogomyakov, A. S.; Ovcharenko, V. I.; Zueva, E. M. Inorg. Chem. 2017, 56, 9825.
	(g) Halbach, R. L.; Nocton, G.; Amaro-Estrada, J. I.; Maron, L.; Booth, C. H.; Andersen, R. A. Inorg. Chem. 2019, 58, 12083.
	(h) Xiao, Y.; Sun, R.; Liang, J.; Fang, Y.; Liu, Z.; Jiang, S.; Wang, B.; Gao, S.; Huang, W. Inorg. Chem. Front. 2021, 8, 2591.
	(i) Stennett, C. R.; Nguyen, J. Q.; Ziller, J. W.; Evans, W. J. Organometallics 2023, 42, 696.
	(j) Zhu, S.; Wu, W.; Hong, D.; Chai, F.; Huang, Z.; Zhu, X.; Zhou, S.; Wang, S. Inorg. Chem. 2024, 63, 14860.
[11]	(a) Ren, W.; Zi, G.; Walter, M. D. Organometallics 2012, 31, 672.
	(b) Ren, W.; Song, H.; Zi, G.; Walter, M. D. Dalton Trans. 2012, 41, 5965.
	(c) Ren, W.; Lukens, W. W.; Zi, G.; Maron, L.; Walter, M. D. Chem. Sci. 2013, 4, 1168.
	(d) Berthet, J.-C.; Thuéry, P.; Ephritikhine, M. C. R. Chim. 2014, 17, 526.
	(e) Yang, P.; Zhou, E.; Fang, B.; Hou, G.; Zi, G.; Walter, M. D. Organometallics 2016, 35, 2129.
	(f) Garner, M. E.; Hohloch, S.; Maron, L.; Arnold, J. Organometallics 2016, 35, 2915.
	(g) Garner, M. E.; Hohloch, S.; Maron, L.; Arnold, J. Angew. Chem., Int. Ed. 2016, 55, 13789.
	(h) Wang, D.; Heng, Y.; Li, T.; Zi, G.; Walter, M. D. Organometallics 2024, 43, 1557.
	(i) Wang, S.; Wang, D.; Heng, Y.; Li, T.; Ding, W.; Zi, G.; Walter, M. D. Inorg. Chem. 2024, 63, 7473.
	(j) Xu, H.; Lv, Z.-J.; Chen, X.; Xi, Z.; Wei, J. Inorg. Chem. 2024, 63, 5530.
	(k) Wang, D.; Heng, Y.; Li, T.; Ding, W.; Hou, G.; Zi, G.; Walter, M. D. Inorg. Chem. 2024, 63, 19188.
	(l) Heng, Y.; Cao, X.-Y.; Dou, Y.-C.; Wang, D.-W.; Yang, P.-K.; Zi, G.-F. Chin. J. Org. Chem. 2026, 46, 2249 (in Chinese).
	(衡义, 曹小英, 豆允灿, 王东伟, 杨丕堃, 自国甫, 有机化学, 2026, 46, 2249.)
[12]	(a) Kraft, S. J.; Walensky, J.; Fanwick, P. E.; Hall, M. B.; Bart, S. C. Inorg. Chem. 2010, 49, 7620.
	(b) Mohammad, A.; Cladis, D. P.; Forrest, W. P.; Fanwick, P. E.; Bart, S. C. Chem. Commun. 2012, 48, 1671.
	(c) Diaconescu, P. L.; Cummins, C. C. Dalton Trans. 2015, 44, 2676.
	(d) Fortier, S.; Veleta, J.; Pialat, A.; Le Roy, J.; Ghiassi, K. B.; Olmstead, M. M.; Metta-Magaña, A.; Murugesu, M.; Villagrán, D. Chem. Eur. J. 2016, 22, 1931.
	(e) Rosenzweig, M. W.; Heinemann, F. W.; Maron, L.; Meyer, K. Inorg. Chem. 2017, 56, 2792.
	(f) Wang, S.; Wang, D.; Li, T.; Heng, Y.; Hou, G.; Zi, G.; Walter, M. D. Organometallics 2022, 41, 1543.
	(g) Wang, S.; Li, T.; Heng, Y.; Wang, D.; Hou, G.; Zi, G.; Walter, M. D. Inorg. Chem. 2022, 61, 6234.
	(h) Heng, Y.; Li, T.; Wang, D.; Hou, G.; Zi, G.; Walter, M. D. Organometallics 2023, 42, 91.
	(i) Li, T.; Wang, D.; Heng, Y.; Hou, G.; Zi, G.; Walter, M. D. Organometallics 2023, 42, 392.
	(j) Cao, X.-Y.; Heng, Y.; Wang, D.-W.; Yang, P.-K.; Hou, G.-H.; Zi, G.-F. Chin. J. Org. Chem. 2026, 46, 1939 (in Chinese).
	(曹小英, 衡义, 王东伟, 杨丕堃, 侯国华, 自国甫, 有机化学, 2026, 46, 1939.)
[13]	(a) Soo, H. S.; Diaconescu, P. L.; Cummins, C. C. Organometallics 2004, 23, 498.
	(b) Bowman, A. C.; England, J.; Sproules, S.; Weyhermüller, T.; Wieghardt, K. Inorg. Chem. 2013, 52, 2242.
	(c) Kawakita, K.; Kakiuchi, Y.; Beaumier, E. P.; Tonks, I. A.; Tsurugi, H.; Mashima, K. Inorg. Chem. 2019, 58, 15155.
[14]	Zhang, L.; Zhou, H.; Bai, S.; Li, S. Dalton Trans. 2021, 50, 3201.
[15]	Zhang, L.; Zheng, L.; Zhao, J. Inorg. Chem. 2025, 64, 855.
[16]	(a) LaPointe, R. E.; Wolczanski, P. T.; Mitchell, J. F. J. Am. Chem. Soc. 1986, 108, 6382.
	(b) Neithamer, D. R.; Parkanyi, L.; Mitchell, J. F.; Wolczanski, P. T. J. Am. Chem. Soc. 1988, 110, 4421.
	(c) Steffey, B. D.; Chamberlain, L. R.; Chesnut, R. W.; Chebi, D. E.; Fanwick, P. E.; Rothwell, I. P. Organometallics 1989, 8, 1419.
[17]	(a) Figueroa, J. S.; Cummins, C. C. J. Am. Chem. Soc. 2003, 125, 4020.
	(b) Etienne, M.; Cafagna, C.; Lorente, P.; Mathieu, R.; de Montauzon, D. Organometallics 1999, 18, 3075.
[18]	Mashima, K.; Matsuo, Y.; Tani, K. Organometallics 1999, 18, 1471.
[19]	Matsuo, Y.; Mashima, K.; Tani, K. Angew. Chem., Int. Ed. 2001, 40, 960.
[20]	(a) Werner, H. Coord. Chem. Rev. 1982, 43, 165.
	(b) Gambarotta, S.; Fiallo, M. L.; Floriani, C.; Chiesi-Villa, A.; Guastini, C. Inorg. Chem. 1984, 23, 3532.
[21]	Gómez, M.; González-Pérez, J. I.; Hernández-Prieto, C.; Martín, A.; Mena, M.; Santamaría, C.; Temprado, M. Inorg. Chem. 2019, 58, 5593.
[22]	Prakash, R.; Haridas, A.; Bakthavachalam, K.; Roisnel, T.; Halet, J.-F.; Ghosh, S. Dalton Trans. 2021, 50, 4036.
[23]	Carbó J. J.; Gómez, M.; Hernández-Prieto, C.; Hernán-Gómez, A.; Martín, A.; Mena, M.; Puiggalí-Jou, J.; Ricart, J. M.; Santamaría, C. Inorg. Chem. 2023, 62, 10100.
[24]	(a) Eisenberger, P.; Ayinla, R. O.; Lauzon, J. M. P.; Schafer, L. L. Angew. Chem., Int. Ed. 2009, 48, 8361.
	(b) Zhang, F.; Song, H.; Zi, G. Dalton Trans. 2011, 40, 1547.
	(c) Batke, S.; Sietzen, M.; Wadepohl, H.; Ballmann, J. Inorg. Chem. 2017, 56, 5122.
[25]	Chisholm, M. H.; Huffman, J. C.; Rothwell, I. P.; Bradley, P. G.; Kree, N.; Woodruff, W. H. J. Am. Chem. Soc. 1981, 103, 4945.
[26]	Kriegel, B. M.; Kaltsoyannis, N.; Chatterjee, R.; Bergman, R. G.; Arnold, J. Organometallics 2017, 36, 3520.

钽联吡啶化合物与腈、异(硫)氰酸酯和碳二亚胺的反应性研究