Answer:
Alkylation reaction help in formation of thiol R-SH
Say lets take sodium hydrosulfide (NaSH) and alkyl chloride (R-Cl)/ any acid like chloroaceic acid or choloro or potassim acetates.
R-Cl + NaSH --> R-SH + NaCl
Such reactions are seen in the production of paper from wood pulp and in the production of organic compounds like thioglycolic acids (TGA)