Help   About ProQuest | 

Dissertations & Theses
The world's most comprehensive collection of dissertations and theses.Learn More...

Citation/Abstract

Print  |  Email  |  Order a Copy  
Zirconium-catalyzed carbomagnesation reaction development and application in synthesis
by Houri, Ahmad Farouk, Ph.D., Boston College, 1996, 246 pages; AAT 9707876

Abstract (Summary)

Chapter I. The chemistry and catalytic activity of $\rm Cp\sb2ZrCl\sb2$ is reviewed, particularly in connection with its interaction with Grignard reagents. The most recent advances in carbon-carbon bond formation by the addition of alkyl magnesium halide reagents to olefins in the presence of $\rm Cp\sb2ZrCl\sb2$ as a catalyst is discussed. Additionally, the use of zirconium based catalysts to facilitate intramolecular diene cyclization is presented.

Chapter 2. The development of the zirconium-catalyzed carbomagnesation of unactivated olefins into a diastereoselective reaction is achieved. High levels of diastereoselectivity were obtained for allylic and homoallylic alcohols and ethers. The mechanism of this reaction was initially studied using norbornenol as a mechanistic probe. The rigidity of this system enabled us to draw significant mechanistic conclusions. The mechanism of the zirconium-catalyzed carbomagnesation of acyclic substrates was then studied. The identity of the active catalyst, mechanism of alkylation and origin of selectivity in zirconacyclopentane cleavage were thoroughly investigated.

Chapter 3. The first synthesis of the aglycon portion of the antifungal agent sch 38516 was accomplished applying our newly developed diastereo- and enantioselective carbomagnesation reactions, in addition to a variety of other new catalytic reactions. The synthesis was accomplished in 13 steps, nine of which employed metal catalysis. Two new tandem catalytic reactions were discovered and a novel Molybdenum catalyzed macrocyclic metathesis was performed.

Indexing (document details)

Advisor:Hoveyda, Amir H.
School:Boston College
School Location:United States -- Massachusetts
Source:DAI-B 57/10, p. 6264, Apr 1997
Source type:Dissertation
Subjects:Organic chemistry
Publication Number: AAT 9707876
ISBN:9780591151688
Document URL:http://proquest.umi.com/pqdlink?did=739506161&Fmt=7&clientId =79356&RQT=309&VName=PQD
ProQuest document ID:739506161


 

 » Purchase the full text

Dissertations and theses can be purchased in a variety of formats which may include: PDF for web download, softcover, hardcover, or microform. Click the "Order a Copy" button to see the formats available for this item.

Print  |  Email  |  Order a Copy  
^Back to Top
Copyright © 2009 ProQuest LLC. All rights reserved. Terms and Conditions