The Synthesis and Characterization of Some Ir(III) Dicationic Complexes

The complex [IrH(COD)(PMe3)3][Cl]2o2HCl was prepared by the reaction between [Ir(COD)(PMe3)3]Cl and HCl gas in methylene chloride. The product precipitated from the solution and is soluble in polar solvents such as water, acetonitrile, and acetone. [IrH(COD)(PMe3)3][Cl]2o2HCl undergoes reaction in water to form fac-IrCl3(PMe3)3. Also, other [IrH(COD)(PMe3)3][X]2 salts were prepared with X being PF6, OTF, or BF4. It was determined that each salt retained a certain amount of excess acids and [IrH(COD)(PMe3)3][OTF]HOTf was the most stable in the solvent acetonitrile while [IrH(COD)(PMe3)3][PF6]2 showed signs of reaction in acetonitrile after 4 hours. The dicationic salts were also reductively deprotonated by DMSO to form the Ir(I) starting material. Finally a slow equilibrium was noted for [IrH(COD)(PMe3)3][BF4]2 in water by the observation of the reductive deprotonation product. The grignard reaction was employed to synthesize Ir(CH3)3(PMe3)3. IrCl3(PMe3)3 reacts with methyl grignard in THF/Benzene to form fac-Ir(CH3)3(PMe3)3. Only the facial isomer of this reaction was observed and the product was soluble in nonpolar solvents. Acidolysis was utilized to synthesize fac-IrCH3Cl2(PMe3).3 from the reaction between Ir(CH3)3(PMe3)3 and 2 equivalents of HCl. Ir(III) methyl dications have also been synthesized by the reaction of 2 equivalents triflic acids with fac-Ir(CH3)3(PMe3)3. The product of the reaction, mer-IrCH3(OTf)2(PMe3)3 was used to study the insertion of alkynes into the Iridium methyl bond. IrHCl2(PMe3)3 was synthesized by the careful acidolysis of IrH2Cl(PMe3)3 using 1 equivalent of HCl. IrH(OTf)2(PMe3)3 was also synthesized by the metathesis of IrHCl2(PMe3)3 with 2.04 equivalents of silver triflate. The product of that reaction, IrH(OTf)2(PMe3)3, has been used to form dimers and trimers of styrene via catalysis and to isomerize alkene alcohols to aldehydes. IrH(OTf)2(PMe3)3 was also used as a polymerization initiator for vinyl and allyl ethers.

Name thesis:degree_name

Ph. D.

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Chemistry

Department dc:contributor.department

Chemistry

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1998

Author dc:creator

• Franks, Marion A.

Chair dc:contributor.committeechair

• Merola, Joseph S.

Committee members dc:contributor.committeemember

• Tanko, James M.
• Anderson, Mark R.
• Hanson, Brian E.
• Brewer, Karen J.

• Oligomerization
• Iridium
• Catalysis
• Water-Soluble
• Polymerization

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

etd-121098-123742

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/30039