Synthesis and Structure of Unprecedented Samarium Complex with Bulky Bis‐iminopyrrolyl Ligand via Intramolecular C=N Bond Activation

• Published in: Zeitschrift für anorganische und allgemeine Chemie (1950) Vol. 643; no. 24; pp. 2144 - 2148
• Main Authors: Das, Suman, Anga, Srinivas, Harinath, Adimulam, Pada Nayek, Hari, Panda, Tarun K.
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 29-12-2017
• Subjects: Coordination compounds; Crystal structure; C–C bond formation; Diffraction; Iminopyrrole; Intramolecular; Ligands; Molecular structure; Samarium; Single crystals; X‐ray diffraction
• ISSN: 0044-2313; 1521-3749
• DOI: 10.1002/zaac.201700354

An unprecedentate samarium complex of the molecular composition [{κ3‐{(Ph2CH)N=CH}2C4H2N)}{κ3‐{(Ph2CHN=CH)(Ph2CHNCH)C4H2N}Sm}2] (2), which was isolated by the reaction of a potassium salt of 2,5‐bis{N‐(diphenylmethyl)‐iminomethyl}pyrrolyl ligand [K(THF)2{(Ph2CH)N=CH}2C4H2N)] (1) with anhydrous samarium diiodide in THF at 60 °C through the in situ reduction of imine bond is presented. The homoleptic samarium complex [[κ3‐{(Ph2CH)–N=CH}2C4H2N)]3Sm] (3) can also be obtained from the reaction of compound 1 with anhydrous samarium triiodide (SmI3) in THF at 60 °C. The molecular structures of complexes 2 and 3 were established by single‐crystal X‐ray diffraction analysis. The molecular structure of complex 2 reveals the formation of a C–C bond in the 2,5‐bis{N‐(diphenylmethyl)iminomethyl}pyrrole ligand moiety (Ph2Py–). However, complex 3 is a homoleptic samarium complex of three bis‐iminopyrrolyl ligands. In complex 2, the samarium ion adopts an octahedral arrangement, whereas in complex 3, a distorted three face‐centered trigonal prismatic mode of nine coordination is observed around the metal ion.