2007 Fiscal Year Final Research Report Summary
Catalyst Design Based on Functionalized Phosphines with a Compact Coordination Center
| Project/Area Number |
18350047
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Synthetic chemistry
|
|---|
| Research Institution | Hokkaido Univesity |
|---|
Principal Investigator |
SAWAMURA Masaya Hokkaido Univesity, Faculty of Science, Professor (40202105)
|
|---|
| Project Period (FY) |
2006 – 2007
|
| Keywords | homogeneous catalysts / heterogeneous catalysts / phosphines / hydrosilylation / hydrogenation / C-H activation / gold catalysts / alkynes |
|---|
| Research Abstract |
1. Research with Caged Phosphine SMAP
The procedure for the synthesis of Ph-SMAP, the parent compound for various SMAP derivatives, was improved. It was confirmed that Ph-SMAP is an excellent ligand for hydrosilylation and hydrgenation of ketones.
SMAP was immobilized on silica gel surface. Silica-SMAP thus obtained showed very high ligand performance for the Rh-catalyzed hydrosilylation and hydrogenation of sterically demanding ketones.Furthermore, Silica-SMAP was successfully used for the development of Ir-catalyzed directed ortho borylation of functionalized arenes.
SMAP derivatives bearing an alkanethiol pendant at the bridgehead silicon atom was prepared and used for the preparation of self-assembled monolayer on gold surface. Au-SMAP thus prepared showed remarkably high activity and turnover efficiency in the Rh-catalyzed dehydrogenative alcohol silylation.
2. Research with Semihollow Trialkynylphosphines
Triethynylphosphine ligands with different end-cap groups were synthesized. Those with bulky end-caps showed unique coordination properties to form 1:1 metal-phosphine complexes selectively with various transition metal species. The semihollow-shaped triethynylphosphines showed extraordinally high accelerating effect in the Rh-catalyzed hydrosilylation of ketones. Furthermore, the semihollow triethynylphosphines were successfully used as ligands for gold-catalyzed alkyne cyclizations. In particular, the accelerating effect in the 6-exo-dig and 7-exo-dig cyclization was remarkable. In addition, this catalyst system enabled unprecedented cyclizations of internal alkyne derivatives.
|
