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Title: Crystal structures of two (5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane)iron(III) complexes
Reported in this contribution are the synthesis and crystal structures of two new Fe III complexes of 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane (HMC), namely, dichlorido(5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane)iron(III) chloride, [FeCl 2 (C 16 H 36 N 4 )]Cl or cis -[FeCl 2 ( rac -HMC)]Cl ( 1 ), and dichlorido(5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane)iron(III) tetrachloridoferrate, [FeCl 2 (C 16 H 36 N 4 )][FeCl 4 ] or trans -[FeCl 2 ( meso -HMC)][FeCl 4 ] ( 2 ). Single-crystal X-ray diffraction studies revealed that both 1 and 2 adopt a pseudo-octahedral geometry, where the macrocycles adopt folded and planar geometries, respectively. The chloride ligands in 1 are cis to each other, while those in 2 have a trans configuration. The relevant bond angles in 1 deviate substantially from an ideal octahedral coordination geometry, with the angles between the cis substituents varying from 81.55 (5) to 107.56 (4)°, and those between the trans -ligating atoms varying from 157.76 (8) to 170.88 (3)°. In contrast, 2 adopts a less strained configuration, in which the N—Fe—N angles vary from 84.61 (8) to 95.39 (8)° and the N—Fe—Cl angles vary from 86.02 (5) to 93.98 (5)°.  more » « less
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Author(s) / Creator(s):
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Date Published:
Journal Name:
Acta Crystallographica Section C Structural Chemistry
Page Range / eLocation ID:
1509 to 1516
Medium: X
Sponsoring Org:
National Science Foundation
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