Organomercury, -rhodium and -palladium intermediates in organic synthesis

Thumbnail Image
Date
1985
Authors
Narayanan, Krishnaswamy
Major Professor
Advisor
Committee Member
Journal Title
Journal ISSN
Volume Title
Publisher
Altmetrics
Authors
Research Projects
Organizational Units
Organizational Unit
Journal Issue
Is Version Of
Versions
Series
Department
Chemistry
Abstract

Chapter I describes the synthesis of arylolefins in fair to good yield by the cross-coupling reaction of arylmercurials and vinyl halides catalyzed by 10% ClRh(PPh(,3))(,3). The reaction appears to involve initial oxidative addition of the vinyl halide to the rhodium(I) catalyst to yield a vinyl rhodium(III) species and subsequent arylation by the organomercurial to generate an aryl vinyl rhodium(III) intermediate which reductively eliminates the olefin and regenerates the catalyst;Chapter II details an improved, stereospecific synthesis of vinylmercurials from alkynes using catecholborane, followed by mercuric acetate plus sodium acetate. A vinylmercurial useful in prostaglandin synthesis is prepared using this procedure;Chapter III summarizes our efforts towards the total synthesis of brefeldin-A using the reaction of a vinylpalladium species with cyclopenetene derivatives as a first key step. Even though the reactions lead to the expected product(s), the yields could not be optimized. An alternative approach using the reaction of a vinylcuprate with cyclopentadiene monoepoxide also leads to the expected key intermediate, but the yield again could not be optimized;In Chapter IV, new synthetic methodology is developed for the synthesis of an ethano-bridged prostaglandin endoperoxide analogue using the selective ozonolysis of a double bond in the presence of an acetylenic bond as a key step. The second part of Chapter IV details our unsuccessful efforts to synthesize an etheno-bridged prostaglandin endoperoxide analogue by the reaction of soft carbanions with nonbornadiene-palladium dichloride.

Comments
Description
Keywords
Citation
Source
Subject Categories
Copyright
Tue Jan 01 00:00:00 UTC 1985