Synthesis and electrochemistry of di-η 5-cyclopentadienyltungsten(IV) and -molybdenum(IV) crown ether complexes

Abstract

Reaction of Na 2[SCH 2(CH 2OCH 2) 3CH 2S] ( 1) with [W(η 5-C 5H 5) 2Cl 2] ( 2) yielded the metalla-crown ether complex [W{SCH 2(CH 2OCH 2) 3CH 2S}(η-C 5H 5) 2] ( 3). Compound 3 undergoes a reversible one-electron redox reaction, the E 1 2 of which was insensitive to the presence of alkali metal cations. The new compounds, [M(η 5-C 5H 5) 2(4-thiobenzo-15-crown-5) 2] (M = Mo, 5; M = W, 6) were prepared by the reaction of the sodium salt of 4-thiobenzo-15-crown-5 with [M(η 5-C 5H 5) 2Cl 2] ( 4) or 2, respectively. These complexes also exhibited reversible electrochemistry, the E 1 2 of which was quite sensitive to the presence of alkali metal cations.