Title page for ETD etd-5217143049751491


Type of Document Master's Thesis
Author Kang, Jianxing
URN etd-5217143049751491
Title Water Soluble Phosphines, Their Transitional Metal Complexes, and Catalysts
Degree Master of Science
Department Chemistry
Advisory Committee
Advisor Name Title
Brian E. Hanson Committee Chair
Karen J. Brewer none
Paul A. Deck none
Keywords
  • water-soluble phosphines
  • two-phase
  • hydroformylation
  • olefins
  • asymmetric hydrogenation
Date of Defense 1997-05-19
Availability unrestricted
Abstract
In recent years two-phase catalysis has been

established as a new field of catalyzed processes

and has achieved industrial-scale importance in

olefin hydroformylation. Two-phase reactions

have a number of advantages, for example, ease

of separation of catalyst and product, catalysts

can be tailored to the particular problem, use of

special properties and effects of water as a

solvent, and low environmental impact. For higher

olefins (* C6), the reaction suffers low activity due

to low water solubility of higher olefins. Tricesium

analog of TPPTS, m,m,m-trisulfonated

triphenylphosphine, was synthesized and fully

characterized. Two-phase olefin hydroformylation

with Rh(acac)(CO)2 was investigated. The results

indicated that both activity and selectivity (linear to

branch aldehyde ratio) are similar to Rh/TPPTS

system. The salt effect showed that increase the

solution ionic strength will increase the selectivity

and decrease the activity in the olefin

hydroformylation with TPPTS. A new surface

active phosphine, trisulfonated

tris-m-(3-phenylpropyl)phenylphosphine, was

synthesized and fully characterized. The results of

biphasic olefin hydroformylation were consistent

with aggregation of the ligand. The two phase

1-octene hydroformylation results showed that

with only 3 methylene groups, there is no

difference between the para and meta position of

C3 group. A new chelating diphosphine,

tetrasulfonated

2,2’-bis{di[p-(3-phenylpropyl)phenyl]phosphinomethyl}-1,1’-biphenyl,

was prepared and fully characterized. Its

application in two-phase hydroformylation of

olefin showed enhanced activity and selectivity

compared to the non-chelated phosphine analog.

Finally, homogeneous asymmetric hydrogenation

was carried out in the presence of a chiral

surfactant in an attempt to affect asymmetric

induction. The catalytic results showed that at a

surfactant/Rh ratio of 25, the asymmetric

hydrogenation of AACA-Me

(a-Acetamidocinnamic Acid Methyl Ester) in

methanol has no effect on asymmetric induction

with the introduction of this chiral surfactant.

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