Regioselective Synthesis of 5‐(Arylsulfanyl)‐ and 5‐(Benzylsulfanyl)‐6‐phenylsalicylates by One‐Pot Cyclizations of 1,3‐Bis(silyloxy)buta‐1,3‐dienes with 2‐(Arylsulfanyl)‐ and 5‐(Benzylsulfanyl)‐3‐ethoxy‐1‐phenylprop‐2‐en‐1‐ones

Abstract

5-(Arylsulfanyl)-6-phenylsalicylates were prepared by one-pot cyclizations of 1,3-bis(trimethylsilyloxy)buta-1,3-dienes with 2-(arylsulfanyl)-3-ethoxy-1-phenylprop-2-en-1-ones.1. Introduction. -Natural and non-natural diaryl sulfides (diaryl thioethers) are of pharmacological relevance and have been isolated as natural products (for dibenzothiophenes, see . Mild metal-catalyzed and metal-free reactions for the synthesis of diaryl sulfides have also been reported [4 -6]. These methods are often limited by the fact that highly substituted and sterically encumbered products are not readily available. In addition, the synthesis of the starting materials, substituted arenes and thiophenols, can be difficult.The use of S-containing building blocks in cyclization reactions (building-block approach) provides an alternative procedure to diaryl sulfides. This approach involves the assembly of the arene moiety by formation of two CÀC bonds. Hilt and co-workers reported an efficient synthesis of diaryl sulfides by Co

“Alkene-to-Alkene” Difunctionalization of Enaminones for the Synthesis of Polyfunctionalized Alkenes by Transition-Metal-Free C–H and C–N Bond Transformation

“…In this context, synthetic methods allowing one-step C–S and C–O bond formation for the synthesis of sulfenyl- and alkoxyl-functionalized alkenes are valuable. In 2010, Langer and co-workers reported a two-step method for the synthesis of α-sulfenyl and β-ethoxyl enones starting from α-bromoketones. The second condensation with HC­(OEt) 3 was run at 140 °C and gave products as the E / Z -mixture (Scheme C).…”