Weston R. Judd

Bio: Weston R. Judd is an academic researcher from University of Kansas. The author has contributed to research in topics: Lewis acids and bases & Alkyl. The author has an hindex of 3, co-authored 6 publications receiving 125 citations.

Remote Control of Diastereoselectivity in Intramolecular Reactions of Chiral Allylsilanes

Abstract: During investigations of cyclization reactions between chiral allylsilanes and N-acyliminium ions, it was discovered that a suitably positioned benzyloxy group on the allylsilane component caused a reversal in the diastereoselectivity of these reactions relative to that normally observed with alkyl-substituted allylsilanes. This effect was subsequently observed in two other reaction types. Investigations into this effect led to the proposal of product formation through thermodynamic control facilitated by neighboring group interactions with a transient cationic species. This hypothesis was experimentally supported by the isolation of an intermediate in the proposed mechanistic pathway.

Organic Azides: An Exploding Diversity of a Unique Class of Compounds

Abstract: Since the discovery of organic azides by Peter Griess more than 140 years ago, numerous syntheses of these energy-rich molecules have been developed. In more recent times in particular, completely new perspectives have been developed for their use in peptide chemistry, combinatorial chemistry, and heterocyclic synthesis. Organic azides have assumed an important position at the interface between chemistry, biology, medicine, and materials science. In this Review, the fundamental characteristics of azide chemistry and current developments are presented. The focus will be placed on cycloadditions (Huisgen reaction), aza ylide chemistry, and the synthesis of heterocycles. Further reactions such as the aza-Wittig reaction, the Sundberg rearrangement, the Staudinger ligation, the Boyer and Boyer-Aube rearrangements, the Curtius rearrangement, the Schmidt rearrangement, and the Hemetsberger rearrangement bear witness to the versatility of modern azide chemistry.

Organische Azide – explodierende Vielfalt bei einer einzigartigen Substanzklasse

Abstract: Seit der Entdeckung der organischen Azide vor uber einhundertvierzig Jahren durch Peter Gries wurde eine Reihe von Synthesen fur diese energiereichen Molekule entwickelt. In letzter Zeit haben sich vollig neue Perspektiven durch Anwendungen in der Peptidchemie, der kombinatorischen Chemie und der Heterocyclensynthese ergeben. Auf dem interdisziplinaren Gebiet zwischen Chemie, Biologie, Medizin und Materialwissenschaften nehmen organische Azide inzwischen einen wichtigen Raum ein. In diesem Aufsatz werden die Grundzuge der Azid-Chemie dargelegt und aktuelle Entwicklungen auf diesem Gebiet beleuchtet. Der Schwerpunkt liegt dabei auf Cycloadditionen (Huisgen-Reaktion), Aza-Ylidchemie und der Synthese von Heterocyclen. Weitere Reaktionen wie die Aza-Wittig-Reaktion, Sundberg-Umlagerung, Staudinger-Ligation, Boyer- und Boyer-Aube-Umlagerung, Curtius-Umlagerung, Schmidt-Umlagerung sowie die Hemetsberger-Umlagerung zeugen von der Vielfaltigkeit moderner Azid-Chemie.

Azide rearrangements in electron-deficient systems.

Abstract: The azide group has a diverse and extensive role in organic chemistry, reflected in the power of azide anion as a strong nucleophile, the role of organic azides as excellent substrates for cycloaddition reactions, the uses of azides as precursors of amines and nitrenes, and azide rearrangements known as the Curtius and Schmidt reactions. In recent years the scope of the Schmidt reaction has begun to be explored in depth, so that it now represents an important reaction in synthetic chemistry. This tutorial review analyses and summarises key recent developments in the field of Schmidt reactions.

Scaffold Diversity from N-Acyliminium Ions

Abstract: N-Acyliminium ions are powerful reactive species for the formation of carbon–carbon and carbon–heteroatom bonds. Strategies relying on intramolecular reactions of N-acyliminium intermediates, also referred to as N-acyliminium ion cyclization reactions, have been employed for the construction of structurally diverse scaffolds, ranging from simple bicyclic skeletons to complex polycyclic systems and natural-product-like compounds. This review aims to provide an overview of cyclization reactions of N-acyliminium ions derived from various precursors for the assembly of structurally diverse scaffolds, covering the literature over the past 12 years (from 2004 to 2015).

Cutting-Edge and Time-Honored Strategies for Stereoselective Construction of C-N Bonds in Total Synthesis.

Abstract: The main objective of this review is to provide a comprehensive survey of methods used for stereoselective construction of carbon–nitrogen bonds during the total synthesis of nitrogen-containing natural products that have appeared in the literature since 2000. The material is organized by specific reaction in order of decreasing number of applications in natural product synthesis. About 800 total syntheses of natural products with stereogenic carbon–nitrogen bonds described since 2000 have been reviewed.