Part 9 : STRUCTURE DETERMINATION

A schematic of the solution is shown below. The information from the question is given in black. Deductions directly from this information are given in red. Points that provide potential key information are shown by green arrows which leads to the structures which are linked via the blue arrows to show the path required to work them all out. There are, of course, other possible thought pathways.

flow chart

Important points:
(1) C is obtained from 2-methylbutane with Br2 / uv tells you that C is 2-bromo-2-methylbutane (3o H most reactive).
(2) Formation of C from B with HBr results in a rearrangement because reaction with PBr3 gives A.
(3) t-butoxide eliminations (tBuO-) often disobey Zaitsev's rule - remove least hindered H, hence C to D.
(4) Alcohol dehydration obeys Zaitsev's rule - hence B to E (more substituted = more stable alkene).
(5) As D, E and F react to give the same alkane, F is deduced (only other alkene variant).
(6) A can be deduced from knowing B or F or based on the chirality information.