01461nas a2200241 4500008004100000022001400041245014600055210006900201260000800270300001400278490000800292520058100300653001600881653002800897653001800925653001800943653002500961100002500986700002801011700002701039700002601066856012701092 2020 eng d a1615-415000aPd-catalyzed annulation of beta-iodovinyl sulfones with 2-halophenols: a general route for the synthesis of 3-sulfonyl benzofuran derivatives0 aPdcatalyzed annulation of betaiodovinyl sulfones with 2halopheno cMAR a1317-13220 v3623 a

The palladium-catalyzed annulation between beta-iodovinyl sulfones and 2-halophenols or 1-bromo-2-naphthol or 2-bromo-3-pyridinol is presented. The annulation process involving oxa-Michael addition-elimination and intramolecular Heck reaction leading to form 2,3-disubstituted benzofurans (aryl benzofuryl sulfones) in good to high yields. The regioselective tandem construction of C-O and C-C bonds has been achieved with a variety of substitution patterns. Moreover, the tandem process is reliable at gram-scale reactions and a plausible mechanism is also proposed.

10aBenzofurans10abeta-Iodovinyl sulfones10aHeck reaction10aNaphthofurans10aoxa-Michael addition1 aReddy, Raju, Jannapu1 aKumar, Jangam, Jagadesh1 aKumari, Arram, Haritha1 aKrishna, Gamidi, Rama uhttps://library.ncl.res.in/content/pd-catalyzed-annulation-beta-iodovinyl-sulfones-2-halophenols-general-route-synthesis-301952nas a2200217 4500008004100000022001400041245018200055210006900237260000900306520106300315653002101378653004201399653001901441653002201460653002301482100002701505700002801532700002601560700002501586856012301611 2021 eng d a0039-788100aNickel-catalyzed difunctionalization of alkynyl bromides with thiosulfonates and N-arylthio succinimides: a convenient synthesis of 1,2-thiosulfonylethenes and 1,1-dithioethenes0 aNickelcatalyzed difunctionalization of alkynyl bromides with thi cAPR 3 a

An efficient nickel-catalyzed vicinal thiosulfonylation of 1bromoalkynes with thiosulfonates in the presence of cesium carbonate is described. An operationally simple and highly regioselective atom transfer radical addition (ATRA) of alkynyl bromides provides a wide range of (E)-1,2-thiosulfonylethenes (alpha-aryl-beta-thioarylvinyl sulfones) in moderate to high yields. The extensive substrate scope of both alkynyl bromides and thiosulfonates is explored with a broad range of functional groups. Indole-derived 1,1- bromoalkenes were also successfully explored in this 1,2-thiosulfonylation process. Moreover, the nickel-catalyzed geminal- dithiolation of alkynyl bromides with N-arylthio succinimides provides 1,1-dithioalkenes in high yields. The present protocol is reliable on gram scale, and a sequential one-pot bromination and thiosulfonylation of phenylacetylene is achieved in a scale-up synthesis. Following control experiments, a plausible mechanism is proposed to rationalize the experimental outcome and the vicinal thiosulfonylation.

10aalkynyl bromides10aatom transfer radical addition (ATRA)10athiosulfonates10athiosulfonylation10avinyl thiosulfones1 aKumari, Arram, Haritha1 aKumar, Jangam, Jagadesh1 aKrishna, Gamidi, Rama1 aReddy, Raju, Jannapu uhttps://library.ncl.res.in/content/nickel-catalyzed-difunctionalization-alkynyl-bromides-thiosulfonates-and-n-arylthio01631nas a2200193 4500008004100000022001400041245015300055210006900208260000900277300001400286490000700300520087800307100002501185700002101210700002801231700002301259700002601282856012901308 2022 eng d a1144-054600aDiethyl phosphite-mediated switchable synthesis of bis(imidazoheterocycles) derived disulfanes and sulfanes using imidazoheterocycles and octasulfur0 aDiethyl phosphitemediated switchable synthesis of bisimidazohete cMAR  a4784-47910 v463 a

A practical and highly efficient oxidative dual C-H sulfenylation of imidazoheterocycles using odorless, inexpensive elemental sulfur in DMSO to synthesize sulfur-bridged imidazoheterocycles under metal-free conditions is reported. The amount of diethyl phosphite and sulfur powder most attractively permits a tunable synthesis of bis(imidazoheterocycle)disulfanes and bis(imidazoheterocycle)sulfanes in good to high yields. A comprehensive substrate scope with a broad range of functional group tolerance was realized, and the efficacy of the process was proved at gram-scale reactions. Next, the bis(imidazopyridine)disulfanes were smoothly reacted with various indoles under similar conditions to form the corresponding imidazo[1,2-a]pyridine-indole-derived thioethers in high yields. A plausible mechanism has been proposed based on the control experiments.

1 aReddy, Raju, Jannapu1 aShankar, Angothu1 aKumar, Jangam, Jagadesh1 aSharadha, Nunavath1 aKrishna, Gamidi, Rama uhttps://library.ncl.res.in/content/diethyl-phosphite-mediated-switchable-synthesis-bisimidazoheterocycles-derived-disulfanes01867nas a2200229 4500008004100000022001400041245017400055210006900229260000900298300001400307490000800321520099000329653003201319653001601351653002001367653002801387653001301415100002501428700002801453700002601481856013001507 2022 eng d a1615-415000aK3PO4-promoted cycloannulation of (E)-beta-Iodovinyl Sulfones with ortho-Hydroxy-chalcones/cinnamates for the synthesis of 2,3,4-trisubstituted 4h-benzopyran derivatives0 aK3PO4promoted cycloannulation of EbetaIodovinyl Sulfones with or cDEC  a4080-40870 v3643 a

K3PO4-mediated cycloannulation of (E)-beta-iodovinyl sulfones with ortho-hydroxy chalcones/ortho-hydroxy cinnamates has been realized to access 2,3,4-trisubstituted-4H-benzopyran derivatives. A metal-free tandem oxa-Michael addition and cycloannulation allows the diversity-oriented synthesis of the corresponding 3-sulfonyl-4H-benzopyrans in good to high yields. More importantly, one-pot three-component reaction between (E)-beta-iodovinyl sulfones, 2-hydroxybenzaldehydes, and phosphonium ylides has been established for the synthesis of 4H-chromene derivatives in moderate to good yields. Notably, this metal-free process features a broad substrate scope and easy elaboration into numerous multifaceted chromene products, including bioactive estrone-derivative. The present protocol is sustainable at the gram scale reactions, and post-synthetic applications were also demonstrated. A plausible mechanism is also presented on the basis of existing experimental results.

10a(E)-beta-Iodovinyl sulfones10aBenzopyrans10aCycloannulation10aortho-Hydroxy Chalcones10aSulfones1 aReddy, Raju, Jannapu1 aKumar, Jangam, Jagadesh1 aKrishna, Gamidi, Rama uhttps://library.ncl.res.in/content/k3po4-promoted-cycloannulation-e-beta-iodovinyl-sulfones-ortho-hydroxy-chalconescinnamates