title: Synthesis and reaction of [[HC(CMeNAr)2]Mn]2 (Ar = 2,6-iPr2C6H3): the complex containing three-coordinate manganese(I) with a Mn-Mn bond exhibiting unusual magnetic properties and electronic structure.
abstract: This paper reports on the synthesis, X-ray structure, magnetic properties, and DFT calculations of [[HC(CMeNAr)2]Mn]2 (Ar = 2,6-iPr2C6H3) (2), the first complex with three-coordinate manganese(I). Reduction of the iodide [[HC(CMeNAr)2]Mn(mu-I)]2 (1) with Na/K in toluene afforded 2 as dark-red crystals. The molecule of 2 contains a Mn2(2+) core with a Mn-Mn bond. The magnetic investigations show a rare example of a high-spin manganese(I) complex with an antiferromagnetic interaction between the two Mn(I) centers. The DFT calculations indicate a strong s-s interaction of the two Mn(I) ions with the open shell configuration (3d54s1). This suggests that the magnetic behavior of 2 could be correctly described as the coupling between two S1 = S2 = 5/2 spin centers. The Mn-Mn bond energy is estimated at 44 kcal mol(-1) by first principle calculations with the B3LYP functional. The further oxidative reaction of 2 with KMnO4 or O2 resulted in the formation of manganese(III) oxide [[HC(CMeNAr)2]Mn(mu-O)]2 (3). Compound 3 shows an antiferromagnetic coupling between the two oxo-bridged manganese(III) centers by magnetic measurements.
authors.affiliation: Institut für Anorganische Chemie der Universität Göttingen, Tammannstrasse 4, D-37077 Göttingen, Germany.
authors.forename: Jianfang
authors.initials: J
authors.lastname: Chai
authors.forename: Hongping
authors.initials: H
authors.lastname: Zhu
authors.forename: A Claudia
authors.initials: AC
authors.lastname: Stückl
authors.forename: Herbert W
authors.initials: HW
authors.lastname: Roesky
authors.forename: Jörg
authors.initials: J
authors.lastname: Magull
authors.forename: Alessandro
authors.initials: A
authors.lastname: Bencini
authors.forename: Andrea
authors.initials: A
authors.lastname: Caneschi
authors.forename: Dante
authors.initials: D
authors.lastname: Gatteschi
mesh_terms: D018360:Crystallography, X-Ray; D004581:Electronics; D008280:Magnetics; D008345:Manganese / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry; D013696:Temperature
chemical_list: D009942:Organometallic Compounds; D008345:Manganese