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Abstract
In this thesis, we will be presenting three different synthetic strategies we attempted to achievethe total synthesis of waihoensene.
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In chapter 1, we describe our attempts at an oxidative coupling approach towards waihoensene
which used a hypervalent iodine mediated oxidative coupling reaction as the key step for
constructing the tetraquinane ring structure followed by a ring expansion to get the carbon ring
framework of the natural product.
In chapter 2, we describe our attempts toward a Rhodium catalyzed C-H activation strategy to
the natural product. Here, we attempted a SmI2 mediated reductive coupling to construct a
bicyclic structure followed by a C-H activation reaction of a diazo compound to generate the
tetraquinane structure.
In chapter 3, we describe our final and successful attempt toward the natural product. In this
route, we employ a Pauson-Khand reaction to construct the carbon ring framework of the natural
product and use quaternary centers as a guide to set the correct stereochemistry at all the chiral
centers of the molecule.
Before our synthesis began, there were no reported synthesis of waihoensene and only Moore’s
synthesis of the waihoensene ring system was published. During our synthetic attempts, Lee’s
first total synthesis was published. Yang’s total synthesis and Tong and Wu’s model study was
published while our manuscript was under review.