Page 189 - Advanced Organic Chemistry Part B - Reactions & Synthesis

Scheme 2.17. (Continued) 161

11 i CH CH + CH 3 CH 3 SECTION 2.4
3 3 Ph PCH Br –
3 3 Olefination Reactions of
KOCR
3 Stabilized Carbon
91% Nucleophiles
100°C, 2 h
CH CH
3 3
O CH 2
b 1) LiBr, THF, –78°C
12
CH CH CH
CH 3 CH OH
CH CH CH CH CH O + CH CH PPh 2 2 2 2
3 2 2 2 3 3
2) BuLi
O, 25°C
3) CH 2 H CH 3
j
13
CHO CO CH
CH + Ph 3 P CCO 2 C H 2 3
3 2 5 CH 3
CH CH CH
3 CH 3 3
3
Boc 85% yield, 92:8 E:Z
CH
14 k 3 CH N CH O
CH 2 + – 3 LiHMDS
P Ph I +
3
CH
OCH 3 O THF/HMPA
3
CH
3 H
CH
2
O 69%
15 l OCH 3 N
satd. K CO , Boc CH
2 3 CH 3
Cl 3
CH 2
O 2 O
+
NC CHO + Ph P CH NC CH CH
3 2
O phase O
transfer
m 100% yield, 72:28 Z:E
16
ArO ArO
+
+ Ph P (CH ) CO H NaHMDS HO CO H
3 2 4 2 toluene 2
O OH
–78°C
Ar = 4-methoxybenzyl 60%
17 n
CH 3 CH CH CH
CH 3 CH CH CH 1)CH Li-LiBr 3 3 3
3
3
3
3
PMBO OMOM
THF - 78°C OTBDMS
PMBO OTBDMS OMOM O CH
CH 2) 3
3
+
P Ph I – TBDMSO CH CH
CH 3 CH 3
3 3 TBDMSO
TBDMSO CH
TBDMSO 3
O
CH 51% 4:1 Z:E
3 O
O CH
3
O
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