A new example of cyclization of (E)-1,5-diarylpent-2-en-4-yn-1-ones to functionalized furan derivatives

Modern Approaches to the Synthesis and Transformations of Practically Valuable Benzothiazole Derivatives

“…2-Mercaptobenzothiazole reacts with aryl enyne ketones in the presence of DBU at room temperature via cyclization to give benzothiazolyl furfuryl sulfides 77a – d [ 112 ]. Cyclization to furans proceeds, apparently, via the intermediate ions ( Scheme 60 ).…”

“…The synthesized scaffolds 75 and 76 are considered pro-drugs that realize their biological activity via the intracell mediators [19]. 2-Mercaptobenzothiazole reacts with aryl enyne ketones in the presence of DBU at room temperature via cyclization to give benzothiazolyl furfuryl sulfides 77a-d [112]. Cyclization to furans proceeds, apparently, via the intermediate ions (Scheme 60).…”

“…The reaction proceeds at room temperature in the absence of bases or phase-transfer catalysts. When carrying out the reaction in the presence of equimolar amounts of iodine required for the formation of triiodide anion, the yield of 2-Mercaptobenzothiazole reacts with aryl enyne ketones in the presence of DBU at room temperature via cyclization to give benzothiazolyl furfuryl sulfides 77a-d [112]. Cyclization to furans proceeds, apparently, via the intermediate ions (Scheme 60).…”

Transformations of Conjugated Enynones in the Superacid CF3SO3H. Synthesis of Butadienyl Triflates, Indanones, and Indenes

“…In particular, 1,5-substituted pent-2-en-4-yn-1-ones 1 (Figure ) add easily N- − and S- − nucleophiles with formation of adducts to the carbon–carbon double or triple bonds. Enynones 1 were explored in the synthesis of various heterocycles, such as furanes, − 1,2,3-triazoles, pyrazols, , aziridines (which may be consequently transformed into pyrroles), and carbocycles through intermediate generation of pyrylium ions, , etc. (Figure ).…”

“…Conjugated enynones 1 and some of their valuable synthetic transformations (selected data from refs − ).…”