Chemistry Reference
In-Depth Information
3
Non Chiral Pauson-Khand Reaction
Takanori Shibata
3.1 History of Co-Mediated Pauson-Khand Reaction
49
3.2 Mechanism of the Pauson-Khand Reaction
50
3.3 An Early Example of Catalytic Reaction
51
3.4 Catalytic Reactions by Aid of Additives
52
3.5 Catalytic Reaction Using
in-situ
Generated Low-Valent
Cobalt Complex
55
3.6 Catalytic Reaction Using Multinuclear Cobalt Carbonyl Catalysts
59
3.7 Catalytic Reaction Using Heterogeneous Catalysts
61
3.8 Catalytic Reaction in Other Than Conventional Solvents
63
3.9 Intramolecular Reaction of Carbodiimides with Alkynes
65
References
66
3.1 History of Co-Mediated Pauson-Khand Reaction
In 1954,I. Wender reported the facile complexation of dicobalt octacarbonyl with alkynes
along with the generation of carbon monoxide.
1
But it took about 20 years for the Pauson-
Khand reaction to be published in a journal. In 1973, P. L. Pauson and I. U. Khand published
the reaction of alkyne-dicobalt hexacarbonyl complex with norbornadiene at 60-70
◦
Cin
1,2-dimethoxyethane (DME), which provided carbonylated tricyclic products (Scheme
3.1).
2
The whole protocol can be categorized as [2
1] cycloaddition of alkyne, alkene
and carbon monoxide. In the early stages, the intermolecular reactions of various alkynes
and alkenes were examined, and synthetically useful cyclic enones were provided. But
+
2
+
