Page 872 - Advanced Organic Chemistry Part B - Reactions & Synthesis

848
Scheme 9.6. Reactions of Allylic Stannanes with Carbonyl Compounds
CHAPTER 9
1 a CH 3 CH 3
Carbon-Carbon H BF 3
Bond-Forming Reactions CH 3 CH 2 CH O + (C 4 H 9 ) 3 SnCH CH CH
of Compounds of Boron, –78°C 3 3
Silicon, and Tin H CH 3 HO 80%
2 b
25°C
) CCH CH
(CH ) C O + CH CHCH Sn(C H ) (CH 3 2 CH
3 2
9 2
2
4
2
24 h 2 2
Cl Cl 75%
3 c 25°C
(CH ) C O + CH Sn(Cl) C H (CH ) CCH CH CH
3 2 2 CHCH 2 2 4 9 3 2 2 2
20 h 70%
OH
4 d OH
(n-C H ) SnCl
CH CHCH O + CH CH CHCH Sn(n-C H ) 4 9 2 2
2 3 2 4 9 3
59%
OH
5 e BF 3
PhCH O + CH 2 CHCHSn(C H ) Ph
4
9 3 –78 °C
70%
OC H 5 OC 2 H 5
2
6 f PhCH O PhCH O CH 3
2
2
H MgBr
CH 3 2
CH O +
H CH Sn(C H )
4
9 3
2
OH
7 g
1) SnF 2 O O
O O + CH CHCH I
2 2
2) CH COCl
3
CHCH CH
CH O 2 CH 2
CH CO 68%
3 2
8 h H CH 3
CH O C CH O
3 2 O O
BF
3
+ CH CH CHCH Sn(C 4 H 9 ) 3
2
3
CH 3 CH 92% yield,
3
94–97% stereoselective
9 i
R SiOCH 2 CH 2 CHCH 2 CH O (n-C H ) SnCH 2 H SnCl 4
3
4
9 3
+
C(CH ) CO CH
CO 2 3 3 CH 3 2 3 –78°C
O
CH SPh CO C(CH )
2
2
3 3
R SiOCH CH CHCH CHCH 2 H
3
2
2
2
OH CH 3 CO CH 3
2
O
CH SPh
55% 2
(Continued)