Question

Define what sulfanes are, how they can be prepared, and find a published scientific journal/article or report that supports this. Polythionates can be viewed as being derivatives of sulfanes, explain.

Answer 1

Sulfanes :

Zero valent sulpfur is called sulfane. It is hexavalent sulphur with no charge. The sulphur atom which can tautomerizes to any thiosulphoxide form.Sulfanes are distributed in crude oil.

Mthods of preparation : Ref: E.J.Muller, J.B.Hyne, Canadian J.Chemistry,46(14), 2341-46(1968)

1)Reaction of Sodium sulphide with hydrochloric acid

NaSx + HCl -------> H₂Sx + 2 NaCl

2nH₂S + nS_xCl₂ ----> nH₂Sx + 2nHCl

Hydrogen polysulphide

2) Reaction of H₂S with sulfur dichloride

   H₂S + Cl-S-Cl ----> H-S-S-Cl + HCl

H-S-S-Cl + H₂S ---> H₂S₂ + HCl

2SCl₂ -----> S₂Cl₂ + Cl₂

HSSCl + H₂Sx ---> H₂S x+^₂ + HCl

Polysulphonates

Polythionates is a the second class of the sulphur -oxygen containing anions . Polythionates are the derivatives of sulfanes represented by the formula S_nO₆^2-where' n 'ranges from 2 to greater than 20. The anion containing more than one sulphur atoms present e.g. S₄O₆^2- is known as tetrathionate.

Tetrathionate is prepared by the reaction of sodium thiosulphate with Iodine

2Na₂S₂O₃ + I₂ ----> Na₂S₄O₆ + 2 NaI