1-butanethiol
(CH_(3)CH_(2)CH_(2)CH_(2)-SH)can be converted to butyl methyl sulfide (
{(
:CH_(3)CH_(2)CH_(2)CH_(2)-S-CH_(3))} in two steps. In the first step, a deprotonation reaction occurs to give a thiolate, which undergoes a methylation reaction with methyl halide as the second step. What reagent would you use for the first deprotonation step?