01558nas a2200157   4500008004100000245015100041210006900192260000800261300001400269490000700283520091300290100002401203700002801227700002201255856012301277       2018                        eng d00aBismuth(III)-catalyzed cycloisomerization and (hetero)arylation of alkynols: simple access to 2-(hetero)aryl tetrahydrofurans and tetrahydropyrans0 aBismuthIIIcatalyzed cycloisomerization and heteroarylation of al  cMAY  a3229-32400 v163 a2-(Hetero)aryl tetrahydrofurans and tetrahydropyrans were successfully synthesized using Bi(OTf)(3)-catalyzed hydroalkoxylation (cycloisomerization) of alkynols (via 5 or 6 exo-dig cyclization) and intermolecular (hetero)arylation. This reaction involves a highly efficient cascade process, where initially the alkynol undergoes a cycloisomerization step via activation of the triple bond and generates the oxocarbenium ion, which subsequently participates in the (hetero)hydroarylation step with electron-rich arenes. Simple to complex suitably functionalized alkynols (4-pentyn-1-ols and 5-hexyn-1-ols) and electron-rich aromatic compounds were found to be reliable substrates in this cascade transformation and furnished a wide range of oxygen heterocycles. This practical tandem process provides a means to build libraries related to pharmacologically active molecules and natural product like scaffolds.1 aNakate, Ashwini, K.1 aPratapure, Madhukar, S.1 aKontham, Ravindar  uhttp://library.ncl.res.in/content/bismuthiii-catalyzed-cycloisomerization-and-heteroarylation-alkynols-simple-access-201561nas a2200217   4500008004100000022001400041245014000055210006900195260000900264300001100273490000800284520076300292653002101055653002201076653002501098653002801123653002101151100002801172700002201200856012101222       2023                        eng d  a0040-403900aBismuth(III)-catalyzed cascade condensation of alkynyl alcohols with terminal alkynes: a facile construction of propargyl cyclic ethers0 aBismuthIIIcatalyzed cascade condensation of alkynyl alcohols wit  cJAN   a1542740 v1143 a<p>
	Herein, we report a Bi(OTf)3-catalyzed cascade condensation between alkynols (particularly pent-4-yn-1ols and hex-5-yn-1-ols) and terminal alkynes (aryl alkynes) to facile access to diverse propargyl cyclic ethers (2 alkynyl tetrahydrofurans and 2 alkynyl tetrahydropyrans). This simple and efficient cascade transformation proceeds through initial intramolecular hydroalkoxylation of alkynols to give corresponding cyclic enol ethers (via exo-dig or endo-dig mode of ring-closure) followed by hydroalkynylation. Costeffective, naturally abundant, green Lewis acid catalysis, ambient reaction conditions, short reaction times, good substrate scope, and high yields are salient features of this strategy.(c) 2022 Elsevier Ltd. All rights reserved.</p>
10aAlkynyl alcohols10aBismuth catalysis10aCascade condensation10aPropargyl cyclic ethers10aTerminal alkynes1 aPratapure, Madhukar, S.1 aKontham, Ravindar  uhttp://library.ncl.res.in/content/bismuthiii-catalyzed-cascade-condensation-alkynyl-alcohols-terminal-alkynes-facile