7200 DOI: 10.1021/la900803a Langmuir 2009, 25(13), 7200–7204 Published on Web 05/22/2009 pubs.acs.org/Langmuir © 2009 American Chemical Society New Catalytic Liquid-Phase Ammoxidation Approach to the Preparation of Niacin (Vitamin B 3 ) Robert Raja,* ,† Richard D. Adams,* ,‡ Douglas A. Blom, ‡ William C. Pearl, Jr., ‡ Enrica Gianotti, § and John Meurig Thomas* , ) † Department of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, U.K., ‡ Department of Chemistry and Biochemistry at the USC Nanocenter, University of South Carolina, Columbia, South Carolina 29208, § Department of Chemistry, IFM and NIS - Centre of Excellence, University of Turin, v.P. Giuria 7, 10125 Torino, Italy, and ) Department of Materials Science, University of Cambridge, Pembroke Street, Cambridge CB2 3QZ, U.K. Received March 5, 2009. Revised Manuscript Received April 2, 2009 New highly dispersed bimetallic nanoscale catalysts based on rhenium combined with antimony or bismuth have been shown to be highly effective for the ammoxidation of 3-picoline to nicotinonitrile (precursor for vitamin B 3 ) under mild conditions in the liquid phase. The use of niacin (3-picolinic acid or nicotinic acid) in food- stuffs and as a cholesterol-lowering agent is extensive. 1 Until very recently, it has been been produced commercially by using procedures 2 that are environmentally aggressive and have serious ecological drawbacks (Schemes 1 and 2). Gas-phase ammoxida- tion (Scheme 3) of 3-picoline to nicotinonitrile (cyanopyridine) followed by hydrolysis to either nicotinamide or nicotinic acid using vanadium oxide catalysts has proved effective and offers an industrially viable strategy for the production of nicotinamide. 2,3 More recently, 4 liquid-phase oxidation processes that involve reacting 3-picoline with homogeneous cobalt and manganese acetates with hydrobromic acid at relatively high temperatures (483 K) and high pressures (100 atm) have been reported. The yields and selectivities are, however, quite low (32% conversion with 19% selectivity for nicotinic acid). Recent studies have also revealed that combinations of rhenium and antimony exhibit activity for the ammoxidation of certain hydrocarbons. 5 Recently, two of us demonstrated 6 that by using a benign source of solid oxygen, namely, acetyl peroxy borate, in conjunc- tion with a single-site microporous catalyst (Mn III AlPO-5) a viable, one-step, solvent-free, environmentally benign prepara- tion of niacin could be formulated. Herein we report a catalytic approach to the synthesis of niacin: an ammoxidation, under mild conditions in the liquid phase with good yields and high selectiv- ities involving compositionally simple (three- or four-atom) nanocluster precursors consisting of Re and either Sb or Bi, in which considerable synergy exists between the constituent elements. In the parlance of industrial chemists, ammoxidation is re- garded as synonymous with the conversion of propylene (usually in a fluid-bed reactor) to acrylonitrile using oxygen and ammonia in the presence of a solid catalyst. 7 Of late, however, a major breakthrough has occurred in the direct ammoxidation of pro- pane to acrylonitrile using a solid catalyst consisting of Mo, V, Nb, Sb, and O. 8 The catalysts used for such purposes are both compositionally and structurally complex, as illustrated by the work of Murayama et al 8a and in a recent U.S. patent by Miyaki et al 7a who describe a catalyst comprising Mo, Bi, at least one element from Ni, Co, Zn, Mg, Mn, and Cu, and at least one element from La, Ce, Pr, and Nd. Trifiro and colleagues 9 have designed a family of rutile-based solid oxide catalysts, typified by Cr 3+ V 4+ Sb 5+ O 6 , that are promising ammoxidation catalysts for converting alkanes directly to nitriles. The method that we describe below is benign, but it first entails the formation of the intermediate, nicotinonitrile, which is easily converted to niacin and niacinamide by hydrolysis. Whereas the single-site heterogeneous catalysts (SSHC) that we used formerly 6 took advantage of the regioselectivity *Corresponding authors. (R.R.) Fax: +44-2380-593781, e-mail: r.raja@ soton.ac.uk. (R.D.A) Fax: +1-803-777-6781, e-mail: adams@mail.chem. sc.edu. (J.M.T.) Fax: +44-1223-740360, e-mail: jmt2@cam.ac.uk. (1) (a) Kirk-Othmer Encyclopedia of Chemical Technology, 4th ed.; Wiley: New York, 1998; Vol. 25, pp 83-89.(b) Ullmann’s Encyclopedia of Industrial Chemistry, 5th ed.; VCH: Weinheim, Germany, 1986; Vol. A27, p 581. (2) Chuck, R. Appl. Catal. A 2005, 280, 75–82. (3) (a) Heveling, J.; Armbruster, E.; Utiger, L.; Rohner, M.; Dettwiler, H.-R. (Lonza) U.S. Patent 5,719,045, 1998. (b) Beschke, H.; Dahm, F. L.; Friedrich, H. (Degussa), Patent DE-OS 3107755, 1982. (4) Hatanaka, M; Tanaka, N. (Nissan Chemical Ind. Ltd.), Patent WO 9305022, 1993. (5) (a) Gaigneaux, E. M.; Liu, H.; Imoto, H.; Shido, T.; Iwasawa, Y. Top. Catal. 2000, 11/12, 185–193. (b) Liu, H.; Gaigneaux, E. M.; Imoto, H.; Shido, T.; Iwasawa, Y. Catal. Lett. 2001, 71, 75–79. (c) Liu, H.; Imoto, H.; Shido, T.; Iwasawa, Y. J. Catal. 2001, 200, 69–78. (6) Raja, R.; Thomas, J. M.; Greenhill-Hooper, M.; Ley, S. V.; Paz, F. A. A. Chem.;Eur. J. 2008, 14, 2340–2348. (7) (a) Miyaki, K.; Yanagita, M.; Mori,K. (Dia-Nitrix Co. Ltd) U.S. Patent 20,044,248,734, 2008. (b) Grasselli, R. K. In Turning Points in Solid-State, Materials and Surface Science; Harris, K. D. M., Edwards, P. P., Eds.; RSC Publishing: London, 2008; pp 577-587(c) Grasselli, R. K.; Buttrey, D. J.; De Santo, P.; Burrington, J. D.; Lugmair, C. G.; Volpe, A. F.; Weingand, T. Catal. Today 2004, 91, 251–258. (d) Sadakane, M.; Ueda, W. In Turning Points in Solid- State, Materials and Surface Science, Harris, K. D. M., Edwards, P. P., Eds.; RSC Publishing: London, 2008; pp 507-518; (e) Guliants, W.; Bhandari, R.; Swami- nathan, B.; Vasudevan, V. K.; Brongersma, H. H.; Knoester, A.; Gaffney, A. M.; Han, S. J. Phys. Chem. B 2005, 109, 24046–24055. (f) Grasselli, R. K. Catal. Today 1999, 49, 141–153. (g) Moro-Oka, Y.; Ueda, W. Adv. Catal. 1994, 40, 233–273. (8) (a) Murayama, H.; Vitny, D.; Ueda, W.; Fuchs, G.; Anne, M .; Dubois, J. L. Appl. Catal. A 2007, 318, 137–142. (b) De Santo, P.; Buttrey, D. J.; Grasselli, R. K.; Lugmair, C. G.; Volpe, A. F.; Toby, B. H.; Vogt, T. Z. Kristallogr. 2004, 219, 152–165. (9) (a) Ballarini, N.; Berry, F. J.; Cavani, F.; Cimini, M.; Ren, X.; Tamoni, D.; Trifiro, F. Catal. Today 2007, 128, 161–167. (b) Trifiro, F. In Fourth International Workshop on Oxide-Based Materials: Novelties and Perspectives; Gamba, A., Fois, E., Tobacchi, G., Eds.; Como, July 6-10, 10; 2008.(c) Ballarini, N.; Cavani, F.; Cimini, M.; Trifiro, F.; Millet, J. M. M.; Cornaro, U.; Catani, R. J. Catal. 2006, 241, 255–267.