Page 1291 - Advanced Organic Chemistry Part B - Reactions & Synthesis

13.9 Use retrosynthetic analysis to suggest syntheses of the following compounds. 1267
Develop at least three outline schemes. Discuss the relative merits of the schemes
PROBLEMS
and develop a fully elaborated synthetic plan for the most promising retrosyn-
thetic scheme.

(a) (b) OH (c) O
CH 2 H O
O CH 2
CH 3
HO CH 3
O CH 3
CH 3 H
CO 2 CH 3
CH 3 CH 3
seychellene brefeldin A pentalenolactone E

13.10. Suggest a method for diastereoselective synthesis of the following compounds:

O 2 CCH 3
(a) (b) OH O (c)
CH 3 CH O
Ph C(CH 3 ) 3
CO 2 H
CH 2
CH 3
CH 3
CH 2 CH 3
CH 3
(d) (e) CH 3
OCHOC 2 H 5
HO CH 3
CO 2 C 2 H 5
Ph
H CH 3
CH 3
OH
13.11. Devise a route that could be used for synthesis of the desired compound in high
enantiomeric purity from the suggested starting material.

(a)
H
C 5 H 9 O O
HO from D-ribose
H

(b) OCH 2 Ph

ArSO 2 N CO 2 C 2 H 5 from ArSO 2 N CH 2 OH
H O H
OCH 2 Ph
(c)
OCH 3
O
from CH 3
CH 3
O