Inorganic Chemistry, Vol.36, No.14, 3064-3071, 1997
Synthesis of bis(Aliphatic-Amine)Osmium(II), bis(Arylamido)Osmium(IV), and bis(Imido)Osmium(VI) and Oxo(Imido)Osmium(VI) Porphyrins
The syntheses, characterization, and reactivity of a series of osmium porphyrins, Os-II(Por)(H2NR)(2) [Por = dianions of octaethylporphyrinato (OEP), tetraphenylporphyrinato (TPP), meso-tetrakis(4-tolyl)porphyrinato (TTP), meso-tetrakis(4-chlorophenyl)porphyrinato (4-Cl-TPP), meso-tetrakis(3,4,5-trimethoxyphenyl)porphyrinato (3,4,5-MeO-TPP), R = Bu-t; For = TPP, R = Pr-i], Os-II(Por)(HNEt2)(2) (For = TPP, 3,4,5-MeO-TPP), Os-IV(Por)(NHAr)(2) (Por = OEP, TPP, 3,4,5-MeO-TPP; Ar = Ph, 4-F-Ph), Os-VI(Por)((NBu)-Bu-t)(2) (Por = TPP, TTP, 4-Cl-TPP, 3,4,5-MeO TPP), (OsO)-O-VI(Por)((NBu)-Bu-t) (For = TPP, TTP, 4-Cl-TPP, 3,4,5-MeO-TPP), and (OsO)-O-VI(Por)(4-F-PhN) (Por = TPP 3,4,5-MeO-TPP) are described. The complexes Os(Por)(HNAr)(2) are prepared from the reactions of Os(Por)-(H-2)(THF) with arylamines in aerobic tetrahydrofuran. Air oxidations of Os(Por)((H2NBu)-Bu-t)(2) in tetrahydrofuran and in the presence of (H2NBu)-Bu-t give OsO(Por)((NBu)-Bu-t) and Os(Por)((NBu)-Bu-t)(2). The X-ray crystal structures of OsO-(TTP)((NBu)-Bu-t) . EtOH and Os(4-Cl-TPP)((NBu)-Bu-t)(2) have been determined. Crystal data for OsO(TTP)((NBu)-Bu-t). EtOH : monoclinic, space group P2(1)/c, a 13.546(6) Angstrom, b = 23.180(3) Angstrom, c = 16.817(3) Angstrom, beta = 90.84(2)degrees, V = 5279.7-(1.0) Angstrom(3), Z = 4. Os(4-Cl-TPP)((NBu)-Bu-t)(2) : monoclinic, space group P2(1)/c, a = 11.046(2) Angstrom, b = 18.380(3) Angstrom, c = 23.640(4) Angstrom, beta = 97.22(1)degrees, V = 4759.8(1.0) Angstrom(3), Z = 4. The Os=O and Os=(NBu)-Bu-t distances in OsO(TTP)-((NBu)-Bu-t) . EtOH are 1.772(7) and 1.759(9) Angstrom, respectively. The Os=(NBu)-Bu-t distances in Os(4-Cl-TPP)((NBu)-Bu-t)(2) average 1.775 Angstrom. The imido angles range from 165.8(8) to 170.6(9)degrees. For the infrared spectra of these complexes, a discussion on the "oxidation state marker" band in the vicinity of 1000 cm(-1) is presented. The differences in the electronic properties of osmium porphyrins at various oxidation states are also described.