Domino Processes of Arynes Reacting with Three Classes of Nucleophiles for Organic Syntheses

Abstract

Synthetic application of arynes is broadened by their reactions with neutral N-, Sand nd O-containing nucleophiles to produce three types of compounds. Accordingly, 1,2-dihydroquinolines are synthesized from Schiff bases, alkynes, and arynes through a Diels-Alder reaction. Epoxides are prepared from thioethers and arynes along with aldehydes or ketones through a Johnson-Corey-Chaykovsky reaction. Phenolic ethers are produced from allyl ethers and arynes through a Claisen-type rearrangement. These target molecules, including natural products γ-asarone, asaricin, and a cholesteryl phenolic ether, are formed through reactions initiated by arynes. These new reactions share a prevailing feature of domino processes, which are carried out in a single flask and afford the desired products in good to high yields.

Asymmetric Synthesis of 3‐Pyrrolines through an Aryne‐Induced Domino Process

“…[25] Arynes [26] are highly reactive species that have been used to initiate domino reactions. [27,28] In addition to a review article of 2013 by Larock et al, [29] recent examples include a threecomponent coupling of benzyne in a carbopalladation reaction; [30] a three-component coupling reaction for the synthesis of benzofurans and coumarins; [31] sequential incorporation of CÀ S, CÀ N, and CÀ C bonds at three consecutive positions of arynes to form various 2,4-disubstituted benzothiazoles; [32] an aryne aza-Diels-Alder reaction and its application to synthesize isoquinolines; [33] conversion of sulfonamides to substituted 1,3-diaminobenzenes. [34] Arynes can also be used to induce the stereospecific olefination of βamino alcohols to alkenes, [35] deoxygenative olefination for the synthesis of deoxy and iminosugars, [36,37] silicon-controlled phenanthrene formation, [38] and a 1,2-addition/(3 + 2) dipolar cycloaddition between azomethine ylides and Schiff bases to yield imidazolidines.…”