2026-09-19T04:05:12Zhttps://dspace.mit.edu/server/oai/requestoai:dspace.mit.edu:1721.1/324782022-01-13T07:54:21Zcom_1721.1_7582com_1721.1_7581col_1721.1_131022
Timothy F. Jamison.
Heffron, Timothy Paul
Massachusetts Institute of Technology. Dept. of Chemistry.
Massachusetts Institute of Technology. Department of Chemistry
2006-03-29T18:48:11Z
2006-03-29T18:48:11Z
2005
2005
http://hdl.handle.net/1721.1/32478
61772167
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2005.
MIT Science Library copy: Issued in leaves, in a 2 v. set.
Also issued in leaves, in a 2 v. set. Vita.
Includes bibliographical references .
I. The Development of Methods for the Iterative Synthesis of Polytetrahydropyrans An iterative method comprising chain homologation, epoxidation, 6-endo cyclization, and protiodesilylation was developed. Notable achievements include the development of a novel propargyl organocopper coupling method, and the complete control of stereoselectivity and regioselectivity during the iterative synthesis of a tristetrahydropyran. The synthesis of the tristetrahydropyran was achieved in 18 total operations. ... (1) homologation (2) epoxidation (3) cyclization (4) protiodesilylation ... II. The Development of a Cascade Synthesis of Polytetrahydropyrans with No Directing Groups at Ring Junctions Cascade approaches to trans-fused tetrahydropyrans were studied. After exploring acid-promoted cascade cyclizations of polyepoxysilanes and polyepoxides without directing groups, the base-promoted cascade cyclization of polyepoxysilanes was realized. In this method, as many as five operations take place in a single step to provide a tristetrahydropyran with no directing groups at any ring junctions. The synthesis of the tristetrahydropyran was accomplished in 11 steps. ...
by Timothy Paul Heffron.
Ph.D.
311 p.
10240856 bytes
10262354 bytes
application/pdf
application/pdf
eng
Massachusetts Institute of Technology
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.
http://dspace.mit.edu/handle/1721.1/7582
Chemistry.
The development of iterative and cascade methods for the rapid synthesis of ladder polyether natural products
Thesis
application/pdf
false
Publication
unknown
unknown
<Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="a8befe7d-45da-4865-bca3-7befda231cb5">
<Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type>
<Language>eng</Language>
<Title>The development of iterative and cascade methods for the rapid synthesis of ladder polyether natural products</Title>
<PublishedIn>
<Publication>
</Publication>
</PublishedIn>
<PublicationDate>2005</PublicationDate>
<Authors>
<Author>
<DisplayName>Heffron, Timothy Paul</DisplayName>
<Affiliation>
<OrgUnit>
</OrgUnit>
</Affiliation>
</Author>
</Authors>
<Editors>
</Editors>
<Publishers>
<Publisher>
<DisplayName>Massachusetts Institute of Technology</DisplayName>
<OrgUnit />
</Publisher>
</Publishers>
<License>http://dspace.mit.edu/handle/1721.1/7582</License>
<Keyword>Chemistry.</Keyword>
<Abstract>I. The Development of Methods for the Iterative Synthesis of Polytetrahydropyrans An iterative method comprising chain homologation, epoxidation, 6-endo cyclization, and protiodesilylation was developed. Notable achievements include the development of a novel propargyl organocopper coupling method, and the complete control of stereoselectivity and regioselectivity during the iterative synthesis of a tristetrahydropyran. The synthesis of the tristetrahydropyran was achieved in 18 total operations. ... (1) homologation (2) epoxidation (3) cyclization (4) protiodesilylation ... II. The Development of a Cascade Synthesis of Polytetrahydropyrans with No Directing Groups at Ring Junctions Cascade approaches to trans-fused tetrahydropyrans were studied. After exploring acid-promoted cascade cyclizations of polyepoxysilanes and polyepoxides without directing groups, the base-promoted cascade cyclization of polyepoxysilanes was realized. In this method, as many as five operations take place in a single step to provide a tristetrahydropyran with no directing groups at any ring junctions. The synthesis of the tristetrahydropyran was accomplished in 11 steps. ...</Abstract>
<Access xmlns="http://purl.org/coar/access_right"
>
</Access>
</Publication>