Spontaneous Formation of an η2‐C, S‐Thioketene Complex in Pursuit of Tungsten(IV)‐Sulfanylalkyne Complexes

Abstract

AbstractThe oxo tungsten(IV) alkyne complexes [Tp′W(O)(I)(η2‐C2Ph2)] (1), [Tp′W(O)(I){η2‐C2(SC2H4SiMe3)2}] (2), and [Tp′W(O)(I){η2‐C2(SBn)2}] (3) [Tp′ = hydridotris(3, 5‐dimethylpyrazolyl)borate, Bn = benzyl] were synthesized from [Tp′W(O)(CO)(I)]. All three compounds were fully characterized including structure determination by X‐ray diffraction analysis. Further elucidation of these reactions led to the isolation of several by‐products including an unexpected tungsten(IV) thioketene complex [Tp′W(O)(I){η2‐S = C=C(H)(SBn)}] (4), which is formed by removal of one Bn group from the alkyne, and dinuclear [Tp′W(O)(I)]2(μ‐O) (6). Both complexes were also fully characterized. X‐ray diffraction analysis reveals an η2‐S, C side‐on binding mode for 4 and a planar O–W–O–W–O moiety for 6. In addition, by changing the solvent from THF to dichloromethane formation of the chiral dihalogen complex [Tp′W(O)(Cl)(I)] (5) was proven.