Synthesis of Thietanes from Saturated Three‐membered Heterocycles

Abstract

Thietanes are important structural motifs of some biological compounds and useful intermediates in organic synthesis. Various synthetic methods of thietanes have been developed recently with readily available saturated three‐membered heterocycles as starting materials or key intermediates. Both saturated three membered heterocycle‐2‐methyl halides and sulfonates and thiiranes are widely utilized materials. Both nucleophilic and electrophilic ring expansions of thiiranes are efficient methods for synthesis of thietanes. In this Focus Review, we have described various strategies for the synthesis of strained four‐membered thiaheterocyclic thietanes from readily available strained and saturated three‐membered heterocycles.

π-Stacking-Controlled Dearomatic Sulfur-Shifted Ene Reaction of Ketenes and Polycyclic Arylthiiranes: Access to Areno[d]-ε-thiolactones

“…Ring-strain-promoted ring opening, ring expansion, and annulation reactions of three-membered saturated heterocycles are an attractive way to introduce three-atom fragments in starting materials . The ring expansions and annulations can construct common, medium, and macrocyclic compounds . Nucleophilic ring expansions of the three-membered saturated heterocycles have been well investigated .…”

“…The ring expansions and annulations can construct common, medium, and macrocyclic compounds . Nucleophilic ring expansions of the three-membered saturated heterocycles have been well investigated . In contrast, only limited approaches for their electrophilic ring expansions have been explored to date .…”

Linear Free Energy Analysis on the Ring‐Expansion of Arylthiiranes with Ketenes

“…[1][2][3][4][5] Nucleophilic ring expansions of saturated three-membered heterocycles have been well studied. [2][3][4][5] However, only limited investigations on their electrophilic ring expansions have been exploited till now. [6][7][8][9] Thiiranes are stronger nucleophilic saturated three-membered heterocycles than oxiranes and aziridines due to their nucleophilic sulfur atom and show excellent reactivity in electrophilic ring expansion with carbenes generated from both diazo compounds [10,11] and sulfonium ylides.…”

From Oxetane to Thietane: Extending the Antiviral Spectrum of 2′-Spirocyclic Uridines by Substituting Oxygen with Sulfur

“…Thietane, the sulfur analogue of the well-known oxetane is an important structural motif found in natural products and pharmacologically active ingredients. 21 A 4′-5′ spirothietane modified sugar analogue was disclosed by Roy et al 22,23 Aiming to identify novel antiviral active nucleoside analogues and extending on our previous work 24−28 we investigated further modifications of the 2′-region of uridine with original spiro-thietane motifs (Figure 1). 29 To the best of our knowledge, no 2′-spirothietane nucleosides have been reported so far.…”

“…Thietane, the sulfur analogue of the well-known oxetane is an important structural motif found in natural products and pharmacologically active ingredients . A 4′-5′ spirothietane modified sugar analogue was disclosed by Roy et al , …”