Regioselective Synthesis of Fluorinated Phenols, Biaryls, 6H‐Benzo[c]chromen‐6‐ones and Fluorenones Based on Formal [3+3] Cyclizations of 1,3‐Bis(silyl enol ethers)

Abstract

A variety of fluorinated phenols, biaryls, 6H-benzo[c]chromen-6-ones and fluorenones were prepared based on regioselective [3+3] cyclizations of 1,3-bis(silyl enol ethers) with 2-fluoro-3-silyloxy-2-en-1-ones.

Triazolopyrimidines as a New Herbicidal Lead for Combating Weed Resistance Associated with Acetohydroxyacid Synthase Mutation

“…1 Intermediates 3 were prepared according to the reported methods. [2][3][4][5][6][7] Scheme 1 Synthetic route of the title compounds 5.…”

Selectfluor and Its Analogs Electrophilic Fluorination for Preparing Alkyl Fluorides

“…12a) [31]. In a onepot procedure under microwave irradiation, a-fluoro-b-keto esters and a-fluoro-1,3-diketones were obtained using Selectfluor and further reacted in Michael additions or Robinson annulations [48,49] or for the synthesis of various fluorinated arenes [50].…”

Reaction of ethyl acetoacetate and 2′-hydroxychalcones: Efficient route to 9-aryl-6<i>H</i>-benzo[c]chromen-6-ones

“…These procedures include the [3+3] cyclizations of 1,3-bis(silyl enol ethers) with 1-(silyloxy)alk-1-en-3-ones [4][5][6], reactions of 3-formylcoumarin with 1,3-bis(silylenol ethers) [7,8], sequential [3+3] Suzuki cyclization reactions [9], Bu 3 SnH mediated radical cyclisation [10], coupling of benzoic acid with benzoquinone using the electrophilic Ir(III) catalyst [11] and the reactions of chromones with 1,3-dicarbonyl compounds [12,13]. There is, therefore, a need to develop synthetically useful methodologies for the preparation of 6H-benzo[c]chromen-6-ones using readily available starting materials.…”