The Chemistry of Azetidin-3-ones, Oxetan-3-ones, and Thietan-3-ones

Abstract

I. Introduction 29 II. The Chemistry of Azetidin-3-ones 29 A. Structural Data 29 B. Synthetic Methods for Azetidin-3-ones 31 B.1. Carbonyl Group Generation in the Azetidine Ring 31 B.2. Intramolecular Cyclization Reactions 34 B.3. 1,3-Dipolar Cycloaddition Reactions 36 C. Chemical Properties of Azetidin-3-ones 37 C.1. Transformations of the Carbonyl Group 37 C.2. Condensation Reactions − Synthesis of 2-Benzylideneazetidin-3-ones 40 C.3. Ring Transformations of Azetidin-3-ones 40 C.4. Miscellaneous 41 III. The Chemistry of Oxetan-3-ones 42 A. Structural Data 42 B. Synthetic Methods for Oxetan-3-ones 43 B.1. Decomposition of Diazoketones 43 B.2. Oxidation Reactions 44 B.3. Intramolecular Displacement Reactions 46 B.4. Miscellaneous 47 C. Chemical Properties of Oxetan-3-ones 48 C.1. Ring Opening and Ring Expansion of Oxetan-3-ones 48 C.2. Transformations of the Carbonyl Group 49 IV. The Chemistry of Thietan-3-ones 50 A. Synthetic Methods for Thietan-3-ones 51 A.1. Synthesis from Acyclic Precursors 51 A.2. Synthesis by Ring Transformations 53 B. Chemical Properties of Thietan-3-ones 54 B.1. Transformations of the Carbonyl Group 55 B.2. Aldol Reactions 56 B.3. Ring Transformations 56 V. Acknowledgments 58 VI. References 58

Functional Polymers Bearing Reactive Azetidinium Groups: Synthesis and Characterization

“…Since 1960, [ 3 ] it is known that primary amines react with epichlorohydrin to give the corresponding chlorohydrin, which subsequently can be transformed to the respective epoxide via addition of base. [ 4 , 5 ] On the other hand, this chlorohydrin can be spontaneously transformed into an azetidinium compound via internal cyclization.…”

Study on Synthesis Of Oxetan-3-ol

“…Chemerda et. al also reported that steroids involving oxetan-3-ones possessed novel bioactivity, such as antiinflammatory and antiglucocorticoid [5]. Owing to the considerable diversity of possible oxetanthe synthetic approaches to oxetan-3-ol was urgent to develop, and actually there are a limited number of routes described.…”

“…Our synthetic route was shown in scheme 1. Our route commenced with commercially available epoxy chloropropane (5). In the presence of catalytic anhydrous Iron (Ш) chloride (without further drying), epoxy chloropropane reacted with acetic acid at 70℃ to give (4) in 90% yield.…”

A Flexible and Stereoselective Synthesis of Azetidin‐3‐ones through Gold‐Catalyzed Intermolecular Oxidation of Alkynes

“…azetidin-2-ones) are a rich source of antibiotics, [2] their structural isomer (azetidin-3-ones) with the carbonyl group one carbon removed from the nitrogen atom, have not been found in nature but could serve as versatile substrates for the synthesis of functionalized azetidines. [3] The synthesis of azetidin-3-ones [3] has been mainly realized by acid-promoted or metal-catalyzed decomposition of a-amino-a'-diazo ketones [4] and 4-exo-tet cyclizations of aamino ketones. The diazo ketone approach is the most reliable in terms of substrate scopes, but it often suffers from competitive reactions and low yields; [4b, 5] moreover, diazo compounds are toxic and potentially explosive.…”

“…Notably, 3 n was formed with 81 % ee from the corresponding sulfinamide (d.r. 91:9), [23] Moreover, the parent N-tert-butylsulfinylazetidin-3-one 3 o was readily prepared using [Et 3 PAuNTf 2 ] as the catalyst [Eq. (2)].…”