Room‐Temperature Electrophilic 5‐endo‐dig Chlorocyclization of Alk‐3‐yn‐1‐ones with the Use of Pool Sanitizer: Synthesis of 3‐Chlorofurans and 5‐Chlorofuropyrimidine Nucleosides

Abstract

The 5-endo-dig chlorocyclization of 1,4-disubstituted alk-3-yn-1-ones (propargylic ketones) with the use of trichloro-striazinetrione (trichloroisocyanuric acid, TCCA; 0.4 equiv.) in toluene, at room temperature, in the absence of base, provides 2,5-disubstituted 3-chlorofurans in high yields (79-96 %). The reaction can be accomplished by using commercially available swimming pool sanitizer. Selected 3-chlo-

Highly Selective Electrophile‐Induced Cascade Reactions between o‐Alkynylbenzaldehydes and Styrene Oxides Leading to the Formation of 1‐Naphthyl Ketones

“…The majority of the reported cascade reactions, trigged by the coordination of alkynes to electrophiles, involve the use of a single starting material containing an alkyne functionality tethered to one more functional group. [9] Upon treatment with electrophiles, coordination to the alkyne initiates a reaction sequence leading to various products. Much more appealing strategies would involve the use of alkynes and nucleophiles/functional groups present in two different substrates.…”

Electrophilic Cyclizations of 2‐Fluoroalk‐3‐yn‐1‐ones: Room‐Temperature Synthesis of Diversely 2,5‐Disubstituted 3,4‐Fluorohalofurans

“…[12][13][14] The electrophilic component serves as both a cyclization catalyst and halogen donor, thus creating a very effective process from the standpoint of material economy.…”

Synthesis and EPR Studies of 2′‐Deoxyuridines with Alkynyl, Rodlike Linkages

“…Such structures, containing a bicyclic base, are known for their highly potent and selective antiviral properties. [xxxi] Furthermore, synthesis of halofuropyrimidines [xxxii] or metallation to dicobalt hexacarbonyl complexes, [xxxiii] with a resulting potential for biological activity, can be envisioned.…”