IRON MACROCYCLIC COMPLEXES - THE SYNTHESIS AND SINGLE-CRYSTAL X-RAY STRUCTURE OF [FE([18]ANEN2S4)](BPH4)2.2MECN.1/2MEOH ([18]ANEN2S4 = 1,4,10,13-TETRATHIA-7,16-DIAZACYCLOOCTADECANE)

Reaction of FeCl2 with one molar equivalent of [18]aneN2S4 in refluxing MeOH-H2O for 15 min affords a deep blue solution containing the complex cation [Fe([18] aneN2S4)] 2+. Addition of excess BF4- or BPh4- counterions gives the complex as a blue solid. A single crystal X-ray structure determination of [Fe([18]aneN2S4)](BPh4) 2· 2MeCN · 1/2MeOH shows iron(II) bound to all six macrocyclic donor atoms in a distorted octahedral geometry, FeN = 2.022(4), 2.037(5), FeS = 2.2578(17), 2.2588(16), 2.2673 (16), 2.2674(15) Å. The macrocycle binds to give a rac configuration with each SCH2CH2 NCH2CH2S linkage bound meridionally to the metal centre. Solutions of [Fe([18]aneN2S4)] (BF4)2 show two irreversible, overlapping oxidations at Epa = + 0.78 and +0.88 V vs Fc/Fc +. © 1990.