Study on the electrospray ionization (ESI) mass spectra of two alkylated thiotungstates [PPh_4][(R-S)WS_3](R=allyl,~tBu)

Two alkylated thiotungstates,[PPh_4][(R-S)WS_3](1∶R=allyl;2∶R=~tBu) in THF were examined by ESI mass spectroscopy.The results showed that besides the presence of the parent [(R-S)WS_3]~- anion, an interesting species,the protonated thiotungstate[(H-S)WS_3]~- anion, was detected to exist in both cases for the first time.