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Title: Geometric isomers of dichloridoiron(III) complexes of CTMC (5,7,12,14-tetramethyl-1,4,8,11-tetraazacyclotetradecane)
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.  more » « less
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Journal Name:
Acta Crystallographica Section C Structural Chemistry
Page Range / eLocation ID:
507 to 514
Medium: X
Sponsoring Org:
National Science Foundation
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