Chemistry Reference
In-Depth Information
Co
2
(CO)
8
(3-5 mol%)
Bu
3
P=S (18-30 mol%)
R
2
Z
Z
O
Benzene, 70 °C
R
1
R
2
CO (1 atm)
R
1
Z = CE
2
, R
1
= R
2
= H: 90%
Z = CE
2
, R
1
= H, R
2
= Me: 90%
Z = NTs, R
1
= R
2
= H: 87%
Z = CE
2
, R
1
= Me, R
2
= H (E/Z= 90/10): 86%(trans/cis = 85/15)
E = CO
2
Et
Co
2
(CO)
8
(3 mol%)
O
Ph
Bu
3
P=S (18 mol%)
Ph
+
Benzene, 70 °C
CO (1 atm)
92%
Scheme 3.12
Chen and Yang reported thiourea as an additive (Scheme 3.13). The Co
2
(CO)
8
-catalyzed
reaction proceeded smoothly in the presence of tetramethylthiourea (TMTU) under am-
bient pressure of carbon monoxide.
13
2) were also
good substrates, and a 5,6-bicyclic system could be constructed. An ester-tethered enyne
was transformed into a bicyclic lactone. An example of the intermolecular reaction of
phenylacetylene with norbornene was also listed.
It is noteworthy that 1,7-enynes (n
=
R
1
Co
2
(CO)
8
(3-10 mol%)
TMTU (18-60 mol%)
R
1
R
2
E
2
C
E
2
C
O
( )
Benzene, 70 °C
n
R
2
CO (1 atm)
R
1
= H, R
2
= H (n = 1): 96%
R
1
= H, R
2
= Me (n = 1): 95%
R
1
= Ph, R
2
= H (n = 1): 91%
R
1
= Me, R
2
= H (n = 1): 95%
R
1
= H, R
2
= H (n = 2): 64%
E= CO
2
Me
S
Me
2
N
NMe
2
TMTU
R
1
R
1
The same as above
R
2
TsN
TsN
O
()
n
R
2
R
1
= H, R
2
= H (n = 1): 95%
R
1
= H, R
2
= Me (n = 1): 90%
R
1
= Ph, R
2
= H (n = 1): 86%
R
1
= Me, R
2
= H (n = 1): 90%
R
1
= H, R
2
= H (n = 2): 84%
O
Co
2
(CO)
8
(10 mol%)
TMTU (60 mol%)
Me
Me
O
O
Benzene, 70 °C
CO (1 atm)
O
O
58%
Scheme 3.13
