News & Events

When

Date - March 22, 2023
1:00 pm - 2:00 pm

What

M.S. Thesis
Department of Chemistry & Biochemistry
UNC Greensboro
Croatt Research Group

Title: “Synthesis of a m-Allyloxy Benzamides and Analyzing Their Effect on the Regioselectivity of the Aromatic Claisen Rearrangement”

Abstract:

The aromatic Claisen rearrangement reaction is an important reaction in the field of synthetic organic chemistry. This reaction involves the rearrangement of allyl group of an allyl phenyl ether to generate an ortho-allyl phenol. In a typical reaction under normal conditions, the allyl group migrates to the less sterically hindered ortho position of the phenyl system. For the system studied herein, certain substrates were found to migrate the allyl group to the more sterically hindered position. To understand this unexpected regioselectivity, a series of substrates were tested in the aromatic Claisen rearrangement.

The synthesis of a variety of amides was completed to analyze their respective effects on the regioselectivity of the aromatic Claisen rearrangement. By doing so, the potential role that a meta amide group would play could be determined to cause the allyl group to be transferred to the more sterically hindered position of the phenyl system.  The research project was accomplished through two main components, synthesizing the amides, and running the Claisen rearrangement reaction to determine the regioselectivity. All of the amides were successfully synthesized with relatively high yields and the Claisen rearrangement reactions were run. Both regioisomers were observed in all cases but in most cases the more sterically hindered one was favored over the less sterically hindered regioisomer, usually in a 2:1 ratio. The relative ratios and yields provided valuable insight into the role that a meta amide could play in the aromatic Claisen rearrangement.