Cobalt-Catalyzed Cross Addition of Silylacetylenes
to Internal Alkynes
Tetsuya Sakurada
Yu-ki Sugiyama
Sentaro Okamoto
10.1021/jo400064b.s001
https://acs.figshare.com/articles/journal_contribution/Cobalt_Catalyzed_Cross_Addition_of_Silylacetylenes_to_Internal_Alkynes/2422306
A CoCl<sub>2</sub>·6H<sub>2</sub>O/Zn reagent using 2-(2,6-diisopropylphenyl)iminomethylpyridine
(dipimp), 1,2-bis(diphenylphosphino)ethane (dppe), or 1,2-bis(diphenylphosphino)benzene
(dppPh) as a ligand effectively catalyzed the cross-addition reaction
of silylacetylene to internal alkynes. The reaction of some unsymmetrical
internal alkynes, such as 3-arylpropargyl alcohols, proceeded in a
highly regioselective manner in the presence of dppe or dppPh but
gave a nearly 1:1 mixture of regioisomers in the presence of dipimp.
The results of reactions using 1-deuterated 2-silylacetylene revealed
that the reaction involves a direct oxidative addition of the silylacetylenic
C–H bond to cobalt.
2016-02-19 11:20:06
dipimp
dppPh
alkyne
presence
regioselective manner
silylacetylene
bi
dppe
oxidative addition