Page 633 - Advanced Organic Chemistry Part B - Reactions & Synthesis

6.4. Apply retrosynthetic analysis to the following transformation and show how 607
each of the target molecules could be prepared from the starting materials given.
PROBLEMS
No more than three separate steps are needed in any of the syntheses.

(a) CH O OCH 3
3
Cl Cl Cl
Cl
Cl Cl Cl +
Cl
CH O OCH 3
3
(b)
O
CH 3
CO CH 3 CH 3 O CH 3
2
CO CH + dimethyl acetylenedicarboxylate
CH 3 2 3
(c)
N(C H )
2 5 2
C(O)Ph 2-butenal, diethylamine,
and trans-1,2-dibenzoylethylene
C(O)Ph
(d)
propenal, 1-butyne and
CH CH C CCH CHCH 2 CH CO CH 3 triethyl orthoacetate
2
2
2
3
(e)
OH OH
HO CH CH CH 2 O
2
O + H C CHCH Br
2
2
O
HO
(f)
CH 3 CO C H
2 2 5
CH 3 CO C H trans-stilbene, diethyl
H Ph 2 2 5 malonate, and acetone
Ph H
(g) CO CH
C 2 3
H 3
CO CH 3 CH 3
2
CHO
CH 3 CH 3 CH 3 CH 3
and any other
necessary reagents
(h)
NO 2
(E)-O NCH CHCO CH 3
2
2
and any other necessary
O CO CH 3 reagents
2
CH
(i) CH 3 3
CH 3
CH 3 CH CH CO C H and any other
CHO
2
2 2 5
2
necessary reagents
(j) CH O CH O
3
3
HO CH CH CH 2 HO CO 2 H
2
CH O CH O
3
3