Dissertation/Thesis Abstract

Multicomponent reactions for the preparation of fluorous tagged pyrimidines and thiopyrimidines and their derivatisation to obtain biaryl-substituted heterocycles
by Piqani, Bruno, M.S., University of Massachusetts Boston, 2011, 188; 1503798
Abstract (Summary)

This thesis presents a work in the field of multicomponent reactions (MCRs), one-step condensation between a fluorous tagged aldehyde, β-keto ester and urea derivatives. This process in literature is known as "Biginelli Reaction". This dissertation describes a new Biginelli reaction element, using fluorous component as a limiting agent.

Chapter one is an introduction of MCRs. A brief historical review, key principles as well as applications in different fields such as academic research, synthetic organic chemistry, and medicinal applications are presented.

Chapter two discusses the general features of the Biginelli reaction, microwave, and fluorous chemistry with a distinctive look from the perspective of green chemistry.

In chapter three our efforts in expanding the procedures to new fluorous components such as fluorous tagged DHMPs are examined. Interesting features for the synthetic process were reveled through multiple types of reagents-controlled synthesis. Suzuki reaction with phenyl boronic acids is explored. The extent of the different structures and the stereochemical preference are discussed. The possibility of Suzuki coupling of thiazolopyrimidine structures by conducting a cycloaddition reaction was investigated. A five member ring was added to the position 2 and 3 of the dihydropyrimidine scaffold to obtain 5 H-Thiazolo 2,3 pyrimidines. Two analogues from cycloaddition reaction were obtained for Suzuki couplings to afford eight final products.

Another feature that we were able to explore was the synthetic manipulation of thiazolopyrimidine adduct obtained from the Biginelli reaction. The reactivity of the double bonded sulfur toward palladium promoted transformations allowed for the synthesis of various heterocycles through Liebeskind-Srogl desulfative coupling followed by Suzuki cross-coupling reactions.

Indexing (document details)
Advisor: Zhang, Wei
Commitee: Carter, Robert, Evans, Jason, Qu, Deyang
School: University of Massachusetts Boston
Department: Chemistry (MS)
School Location: United States -- Massachusetts
Source: MAI 50/03M, Masters Abstracts International
Subjects: Organic chemistry
Keywords: Biginelli reaction, Cyclocondensation, Fluorous chemistry, Multicomponent reaction, Pyrimidines, Thiazolopyrimidines
Publication Number: 1503798
ISBN: 978-1-267-10185-3
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