Your goal is to synthesize a disubstituted alkyne in 4 steps starting with ethyne as the source of your triple bond. Steps 1 and 3 are the steps using sodium amide. Select all of the species that could be used for steps 2 and 4 to accomplish your goal in good yield.
a) isopropyl iodide
b) ethylmagnesium bromide
c) HBr
d) 1-chloro-4-methylpentane
e) ethoxide ion
f) methanol
g) hexan-1-ol
h) bromoethane
i) methyl tosylate
j) iodocyclohexane