research communications Acta Cryst. (2018). E74, 543–547 https://doi.org/10.1107/S2056989018004565 543 Received 16 March 2018 Accepted 19 March 2018 Edited by H. Stoeckli-Evans, University of Neucha ˆtel, Switzerland Keywords: crystal structure; lutetium; organo- phosphate; binuclear complex; coordination compound; acrylonitrile polymerization. CCDC reference: 1830858 Supporting information: this article has supporting information at journals.iucr.org/e Crystal structure and catalytic activity of tetrakis- (l 2 -ethyl 2,6-di-tert-butyl-4-methylphenylphos- phato-j 2 O:O 0 )bis(ethyl 2,6-di-tert-butyl-4-methyl- phenyl phosphato-j 2 O,O 0 )dilutetium n-heptane disolvate Mikhail E. Minyaev, a * Alexander N. Tavtorkin, a,b Sof’ya A. Korchagina, a,b Ilya E. Nifant’ev a,b and Andrei V. Churakov c a A.V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 29 Leninsky prospect, 119991, Moscow, Russian Federation, b Chemistry Department, M.V. Lomonosov Moscow State University, 1 Leninskie Gory Str., Building 3, Moscow 119991, Russian Federation, and c N.S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, 31 Leninsky Prospect, Moscow 119991, Russian Federation. *Correspondence e-mail: mminyaev@mail.ru The title complex, [Lu 2 (C 17 H 28 O 4 P) 6 ]2C 7 H 16 , was formed in the reaction between potassium 2,6-di-tert-butyl-4-methylphenyl ethyl phosphate, [K(2,6- t Bu 2 -4-MeC 6 H 2 -O)(EtO)PO 2 ], and LuCl 3 (H 2 O) 6 in water, followed by vacuum drying and recrystallization from heptane. Its crystal structure has triclinic (P 1) symmetry at 120 K. The lutetium tris(phosphate) complex has a binuclear [Lu 2 (-OPO) 4 ] core and the organophosphate ligand exhibits  2 O,O 0 terminal and  2 - 1 O: 1 O 0 bridging coordination modes with the Lu III ion being sixfold coordinated. The complex is of interest as a precatalyst in the acrylonitrile polymerization process and displays good catalytic activity under mild conditions. 1. Chemical context Over recent decades, rare-earth complexes bearing organic ligands have been widely used as reagents or catalysts in organic synthesis and especially as catalysts or precatalysts in various polymerization processes (Kobayashi & Anwander, 2001; Kobayashi et al., 2002). Rare-earth organophosphates and carboxylates have been successfully applied as catalyst precursors for 1,3-diene polymerization (see Friebe et al. , 2006; Fischbach & Anwander, 2006; Nifant’ev et al. , 2013, 2014; Zhang et al., 2010; Jang et al., 2000; Kwag, 2002; Fischbach et al., 2006; Evans et al. , 2001; Evans & Giarikos, 2004; Roitershtein et al., 2013; Wilson 1993). The use of organic phosphates is not limited to the stereoregular polymerization of conjugated dienes. Various lanthanide complexes have been applied in the polymerization of heteroatomic polar monomers, including polymerization of methyl methacrylate (Jiang et al., 2000), rac- dilactide (Nifant’ev et al. , 2013) and acrylonitrile (Jiang et al., 1997) under mild conditions. Polymerization methods of obtaining polyacrylonitrile or acrylonitrile copolymers with other polar monomers, e.g. methyl acrylate, may require rather hard conditions (supercritical CO 2 medium) (Shlyakhtin et al., 2013; Shlyakhtin et al., 2014a,b,c). The title complex {Lu 2 [(2,6- t Bu 2 -4-MeC 6 H 2 -O)(EtO)- PO 2 ] 6 }2C 7 H 16 (1), was prepared in the reaction between ISSN 2056-9890