Page 971 - Advanced Organic Chemistry Part A - Structure and Mechanisms, 5th ed (2007) - Carey _ Sundberg
P. 971
d. 955
H 2 O, DME PROBLEMS
CHSCH C H O
PhCH 2 CH 2 11 14
reflux, 12 h
CH CH 2
e.
CH CH 2
O K + – Ot Bu
Ph S + CH 3
O
f.
+ CH O CC CCO CH 3
2
2
3
g.
heat
h.
(CH ) C
3 3
+ C C O
NC
i.
CH 2 (C H ) N
2 5 3
CH COCl
2
j.
OSiR 3
heat
CH O
10.8. In the series of bicyclic oxepins 10-A (n = 3 4 5), only the compound with
n = 5 undergoes rearrangement (at 60 C) to the isomeric oxepin 10-B. The
other two compounds (n = 3 or 4) are stable, even at much higher temperature.
When 10-B (n = 3) was synthesized by another route, it showed no tendency
to revert to 10-A (n = 3). Offer an explanation for these observations.
O O (CH 2 )n O O (CH 2 )n
10-A 10-B
