Nickel-catalyzed intermolecular reductive couplings of alkynes and aldehydes ; Enantioselective synthesis of (-)-terpestacin and structural revision of siccanol using catalytic stereoselective fragment couplings and macrocyclizations
Name
56474296-MIT.pdf
Description
Full printable version
Size
4.71 MB
Format
Adobe PDF
Checksum (MD5)
dfea29f0cba457fab0863d5d4d368b83
Author(s)
Chan, Johann, 1976-
Advisor(s)
Timothy F. Jamison.
Alternative Title
Nickel-catalyzed intermolecular reductive couplings of alkynes and aldehydes
Date Issued
2004
Publisher
Massachusetts Institute of Technology
Abstract
I. Nickel-Catalyzed Intermolecular Reductive Coupling of Alkynes and Aldehydes. Alkynes and aldehydes were coupled reductively in a single catalytic reaction to yield di- and trisubstituted allylic alcohols with high stereoselectivity and regioselectivity. In most cases, a 1:1 ratio of alkyne to aldehyde was sufficient for efficient coupling. The yield and regioselectivity were strongly dependent on the phosphine ligand, but the allylic alcohols formed were invariably the products of cis addition to the alkyne. [Image] ... II. Enantioselective Synthesis of (-)-Terpestacin and Structural Revision of Siccanol Using Catalytic Stereoselective Fragment Couplings and Macrocyclizations. (-)-Terpestacin (1), (naturally occurring enantiomer) and (+)-1 -epi-terpestacin (2) were prepared using catalyst-controlled, stereoselective intermolecular reductive couplings of alkyne 9 and aldehyde 10. Related to enantioselective methods developed in our laboratory, these stereoselective fragment couplings were instrumental in confirming that "siccanol" is not 11-epi-terpestacin, but in fact is (-)-terpestacin itself.
Description
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2004.
Vita.
Includes bibliographical references.
Subjects
Chemistry.
MIT Department
Massachusetts Institute of Technology. Department of Chemistry
Terms of Use
M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.
Persistent DSpace Link
