Page 208 - Advanced Organic Chemistry Part B - Reactions & Synthesis

180 Scheme 2.21. Reactions of Sulfur Ylides

CHAPTER 2 a
1 O
Reactions of Carbon O
Nucleophiles with +
–
Carbonyl Compounds DMSO – THF
+ CH S(CH )
2
3 2
0°C
97%
2 a + DMSO – THF C H
–
6 5
C H CHO + CH S(CH ) 75%
2
3 2
6 5
0°C
O
3 b O O O
DMSO
–
+ CH S(CH )
2
+ 3 2 67–76%
4 c CH CH CH 3
CH 3 CH 3 3 O 3 CH 3
–
DMSO
O + CH S(CH ) O
3 2
2
50°C
CH 3 CH 3 67%
5 a CH 3 CH 3
O + DMSO – THF O
–
+ CH S(CH )
3 2
2
0°C
89%
C
H 2 CH 3 H C CH 3
2
CH 3
6 a CH 3 O O
O – +
+ CH S(CH ) DMSO
3 2
2
50°C
C
H 2 CH 3 81%
H C CH 3
2
7 d
+
O CH
O 2
H 2 C O
– + DMSO–THF
ylide: CH S(CH ) 6% 94%
2
3 2
0°C
O
– + DMSO
ylide: CH S(CH ) 65% 27%
3 2
2
60°C
8 e O CH 3 CH 3 CH CH
O 3 3
NaNH
CH C(CH ) CH(CH ) CH(CH ) CH(CH ) 2 (CH 2 ) 3 CH(CH 2 ) 3 CH(CH 2 ) 3 CH(CH 3 ) 2
2 3
3
3 2
2 3
2 3
+
(CH ) S Cl – CH 3
3 3
92%
(Continued)