91Ó°ÊÓ

Write structural formulas and give the IUPAC names for all the alkynes of molecular formula \(\mathrm{C}_{5} \mathrm{H}_{8}\).

How do bond distances and bond strengths change with electronegativity in the series \(\mathrm{NH}_{3}\), \(\mathrm{H}_{2} \mathrm{O}\), and \(\mathrm{HF}\) ?

Outline efficient syntheses of each of the following alkynes from acetylene and any necessary organic or inorganic reagents: (a) 1-Heptyne (b) 2 -Heptyne (c) 3-Hentyne

Which of the alkynes of molecular formula \(\mathrm{C}_{5} \mathrm{H}_{8}\) can be prepared in good yield by alkylation on dialkylation of acetylene? Explain why the preparation of the other \(\mathrm{C}_{5} \mathrm{H}_{8}\) isomers would not be practical.

Give the structures of three isomeric dibromides that could be used as starting materials for the preparation of 3,3 -dimethyl-1-butyne.

Show, by writing an appropriate series of equations, how you could prepare propyne from each of the following compounds as starting materials. You may use any necessary organic or inorganic reagents. (a) 2 -Propanol (d) 1,1-Dichloroethane (b) 1-Propanol (e) Ethyl alcohol (c) Isopropyl bromide

Design a synthesis of 1,1-dichloroethane from each of the following. (a) Ethylene (b) Vinyl chloride \(\left(\mathrm{H}_{2} \mathrm{C}=\mathrm{CHCl}\right)\) (c) 1,1-Dibromoethane

Give the structure of the enol formed by hydration of 2 -butyne, and write a series of equations showing its conversion to its corresponding ketone isomer.

Show by a series of equations how you could prepare 2 -octanone from acetylene and any necessary organic or inorganic reagents. How could you prepare 4-octanone?

A certain hydrocarbon had the molecular formula \(\mathrm{C}_{16} \mathrm{H}_{26}\) and contained two triple bonds. Ozonolysis gave \(\mathrm{CH}_{3}\left(\mathrm{CH}_{2}\right)_{4} \mathrm{CO}_{2} \mathrm{H}\) and \(\mathrm{HO}_{2} \mathrm{CCH}_{2} \mathrm{CH}_{2} \mathrm{CO}_{2} \mathrm{H}\) as the only products. Suggest a reasonable structure for this hydrocarbon.