Synthesis, crystal structure, and thermal behavior of a diiron toluenethiolate complex with triphenylphosphine coligand

Improved Access to ‘Butterfly’ Di‐Iron Dithiolates Fe2(μ‐SR)2(CO)6 and their Mono‐ and Bis(phosphine) Adducts

“…This area has been extensively reviewed, and the interested reader is directly to the many excellent articles covering the ‘butterfly’ systems [4,5] . However, there is now increasing interest in the ‘open’ (unbridged) analogues, which may offer unique reactivity, and which are also potential starting materials for novel chemistry in their own right [6–10] …”

“…[4,5] However, there is now increasing interest in the 'open' (unbridged) analogues, which may offer unique reactivity, and which are also potential starting materials for novel chemistry in their own right. [6][7][8][9][10] Complexes of general formula Fe 2 (μ-SR) 2 (CO) 6 have been synthesised by many methods: (i) treatment of Fe 3 (CO) 12 with RSH derivatives in several hydrocarbon solvents with reflux [11] or photochemically, [12] (the mechanism is believed to involve formation of Fe 3 (CO) 9 (H)(RS) [13] ) (ii) the Hieber-Gruber reaction, [14] (iii) treatment of (C 5 H 4 SPh) 2 Fe with Fe 2 (CO) 9 under photolytic conditions, [15] (iv) reduction of Fe 2 (μ-S) 2 (CO) 6 by Na or KH followed by treatment with alkyl halide to give the corresponding derivatives, [16] (v) treatment of Fe(CO) 5 with RSH or RSSR under CO atmosphere, [17] and (vi) King's method by the reaction of RSSR with Fe 3 (CO) 12 under reflux. [18] Here, we have explored optimisations of King's method and subsequent introduction of phosphine in 'open' systems featuring aromatic and the aliphatic groups at the sulfur centres, and the effect of phosphine substituted on structural parameters, carbonyl stretching, and voltammetry.…”