Development of optically active cyclopentadienyl ruthenium complexes and their application in asymmetric catalysis [electronic resource]
- Meera Rao.
- Physical description
- 1 online resource.
- Novel ruthenium complexes were developed containing a cyclopentadienyl (Cp) ligand tethered to a chiral sulfoxide, which also serves as a ligand. These complexes were synthesized via a [3+2] dehydrogenative cycloaddition between a Ru-[pi]-allyl complex and a terminal acetylene. Using the cycloaddition as a key step, the desired sulfoxide-ligated complexes could be prepared in six linear steps without the use of toxic metallating reagents such as thallium salts. A diverse library of complexes could be accessed through this method, which speaks to the robust nature of the key cycloaddition step. Using these complexes, a CpRu-catalyzed branched-selective asymmetric allylic alkylation (AAA) was developed. Using this method, various oxygen nucleophiles could be alkylated with allyl chloride electrophiles to provide branched ethers, esters and alcohols with high levels of regio- and enantioselectivity. These complexes also were effective in catalyzing an asymmetric redox bicycloisomerization to generate complex [3.1.0]- and [4.1.0]-azabicycles from simple propargyl alcohol substrates.
- Publication date
- Submitted to the Department of Chemistry.
- Thesis (Ph.D.)--Stanford University, 2013.