Synthesis of Sulfur-Rich Crown Ethers via Azide–Alkyne Macrocyclization of α,ω-Diazido- and α,ω-Dipropargyl Sulfide Derivatives

Abstract

A series of diazides and dithiols were prepared in a one-pot protocol from commercially available alcohols by a modified Appel reaction. Selected dithiols were converted into α,ω-dipropargyl sulfides and combined with thioglycol-derived diazides under Huisgen–Sharpless–Meldal reaction conditions to give a new class of 1,2,3-triazole-linked sulfur-rich crown ethers.

Key words

Appel reaction - click [3+2] cycloaddition - macrocycles - crown thioethers - thiiranium salt

• References and Notes

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Diagnostic signals in ¹H NMR spectra located at δ = 2.81–2.84, 2.93–2.98, and 3.76–3.78 ppm could be attributed to the methylene groups neighboring sulfur atom of the intermediates A according to the literature data:
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