Page 1163 - Advanced Organic Chemistry Part A - Structure and Mechanisms, 5th ed (2007) - Carey _ Sundberg

1148 j.
O
CHAPTER 12
Photochemistry Ph H O CCH(CH )
3 2
H
H CCCH(CH 3 2 hv CH 3 H
)
CH 3 acetophenone
CH 3 Ph
CH 3
k.
O
CH CPh
O 2
hv
CPh
H

l.
CH 3 CH 3
hv
O
(CH ) C CHCH CHCH CO H
ether– 3 2 2 2
water
m.
CH 3
O CH 3 H
hv
C C
H CH CCH(CH )
3 2
2
CH(CH )
3 2
CH 2
n.
CO CH 3
2
hv
CH O CC CCO CH 3
2
3
2
benzene
CO CH 3
2
o.
O
hv
PhCH O + CH C CCH 3 PhCH CCCH 3
3
CH 3
12.5. Benzene-sensitized photolysis of methyl 3-cyclohexene-1-carboxylate in
acetic acid leads to addition of acetic to the double bond. Only the trans
adducts are formed. What factor(s) might be responsible for this stereo-
selectivity? Which of the two regioisomers do you expect to be the major
product?

O H H H
hv
CO 2 CH 3 O
CH 3 CO CO 2 CH 3+ CO 2 CH 3
C 6 H 6 ,
CH 3 CO 2 H CH 3 CO
H
5-A 5-B