Question

An alkyne of six carbon atoms gives the same single product in its reaction either with bh3 in thf followed by h2o2 /oh–, or with h2o/hg2 /h3o . draw the structure of the alkyne (containing only carbon and hydrogen atoms).

Answer 1

Answer

3-hexyne.

Explanation:

Hello,

In this case, on the attached picture, you will see how 3-hexyne is firstly hydrated to hex-3-en-3-ol or 3-hexen-3-ol via the two given catalysts which yields the very same single product in terms of nomenclature but differing on the OH position.

Now, due to the high-oxidizing media, an equilibrium is attained between hex-3-en-3-ol and hexan-3-one which again, could be yielded via either of the firstly hydrated species.

Therefore, the requested alkyne is 3-hexyne.

Best regards.

Answer 2

Two compounds containing six carbon atoms on treatment with either with BH₃ in THF followed by H₂O₂ /OH⁻ (OR) with H₂O / Hg²⁺ / H₃O⁺ gives the same products. 
The two alkynes, their two different types of reactons and products are given below,