Both trans and cis iron–CTMC complexes, namely, trans -dichlorido[(5 SR ,7 RS ,12 RS ,14 SR )-5,7,12,14-tetramethyl-1,4,8,11-tetraazacyclotetradecane]iron(III) tetrachloridoferrate, [Fe(C 14 H 32 N 4 )Cl 2 ][FeCl 4 ] ( 1a ), the analogous chloride methanol monosolvate, [Fe(C 14 H 32 N 4 )Cl 2 ]Cl·CH 3 OH ( 1b ), and cis -dichlorido[(5 SR ,7 RS ,12 SR ,14 RS )-5,7,12,14-tetramethyl-1,4,8,11-tetraazacyclotetradecane]iron(III) chloride, [Fe(C 14 H 32 N 4 )Cl 2 ]Cl ( 2 ), were successfully synthesized and structurally characterized using X-ray diffraction. The coordination geometry of the macrocycle is dependent on the stereoisomerism of CTMC. The packing of these complexes appears to be strongly influenced by extensive hydrogen-bonding interactions, which are in turn determined by the nature of the counter-anions ( 1a versus 1b ) and/or the coordination geometry of the macrocycle ( 1a/1b versus 2 ). These observations are extended to related ferric cis - and trans- dichloro macrocyclic complexes.
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Crystal structures of two new six-coordinate iron(III) complexes with 1,2-bis(diphenylphosphane) ligands
Structural characterization of the ionic complexes [FeCl 2 (C 26 H 22 P 2 ) 2 ][FeCl 4 ]·0.59CH 2 Cl 2 or [(dppen) 2 FeCl 2 ][FeCl 4 ]·0.59CH 2 Cl 2 (dppen = cis -1,2-bis(diphenylphosphane)ethylene, P 2 C 26 H 22 ) and [FeCl 2 (C 30 H 24 P 2 ) 2 ][FeCl 4 ]·CH 2 Cl 2 or [(dpbz) 2 FeCl 2 ][FeCl 4 ]·CH 2 Cl 2 (dpbz = 1,2-bis(diphenylphosphane)benzene, P 2 C 30 H 24 ) demonstrates trans coordination of two bidentate phosphane ligands (bisphosphanes) to a single iron(III) center, resulting in six-coordinate cationic complexes that are balanced in charge by tetrachloridoferrate(III) monoanions. The trans bisphosphane coordination is consistent will all previously reported molecular structures of six coordinate iron(III) complex cations with a (PP) 2 X 2 ( X = halido) donor set. The complex with dppen crystallizes in the centrosymmetric space group C 2/ c as a partial-occupancy [0.592 (4)] dichloromethane solvate, while the dpbz-ligated complex crystallizes in the triclinic space group P 1 as a full dichloromethane monosolvate. Furthermore, the crystal studied of [(dpbz) 2 FeCl 2 ][FeCl 4 ]·CH 2 Cl 2 was an inversion twin, whose component mass ratio refined to 0.76 (3):0.24 (3). Beyond a few very weak C—H...Cl and C—H...π interactions, there are no significant supramolecular features in either structure.
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- Award ID(s):
- 1649228
- PAR ID:
- 10080465
- Date Published:
- Journal Name:
- Acta Crystallographica Section E Crystallographic Communications
- Volume:
- 74
- Issue:
- 6
- ISSN:
- 2056-9890
- Page Range / eLocation ID:
- 803 to 807
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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