02095nas a2200217   4500008004100000022001400041245017100055210006900226260011000295300001400405490000700419520116900426100002501595700002001620700002001640700002301660700002201683700002101705700002601726856012501752       2015                        eng d  a1463-926200aHighly efficient regioselective synthesis of pyrroles via a tandem enamine formation-Michael addition-cyclization sequence under catalyst- and solvent-free conditions0 aHighly efficient regioselective synthesis of pyrroles via a tand  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcAPR  a3415-34230 v173 a<p>A convenient catalyst-free, three-component procedure was developed for the synthesis of tetrasubstituted pyrroles under solvent-free conditions and in green solvents glycerol, PEG-200 and water. A sequential enamine-formation, Michael addition and intramolecular cyclization of primary amines, 1,3-dicarbonyl compounds and isatin-derived Michael acceptors afforded 3-(1H-pyrrol-3-yl)indolin-2-ones in excellent yields. In this simple one-pot transformation the requirement of column chromatography purification of the products was completely avoided. Besides, the method is highly environmentally benign and atom-economical, and the only side product of this reaction was two molecules of water. A comparative study for the four developed conditions showed that the solvent-free conditions were superior regardless of the nature of the starting materials, and the green solvents were effective for alkyl and benzylamines affording higher yields compared to arylamines. The preliminary in vitro cytotoxic studies of a representative compound against Ehrlich's ascites carcinoma (EAC) tumor cells showed significant activity with a CTC50 value of 15.64 mu M.</p>1 aVivekanand, Thavaraj1 aVinoth, Perumal1 aAgieshkumar, B.1 aSampath, Natarajan1 aSudalai, Arumugam1 aMenendez, Carlos1 aSridharan, Vellaisamy  uhttps://library.ncl.res.in/content/highly-efficient-regioselective-synthesis-pyrroles-tandem-enamine-formation-michael-001527nas a2200205   4500008004100000022001400041245015000055210006900205260007100274300001400345490000700359520070200366100002001068700002301088700001901111700002201130700001901152700002601171856012401197       2016                        eng d  a1523-706000aPalladium-catalyzed internal nucleophile-assisted hydration-olefin insertion cascade: diastereoselective synthesis of 2,3-dihydro-1H-inden-1-ones0 aPalladiumcatalyzed internal nucleophileassisted hydrationolefin   a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUL  a3442-34450 v183 a<p>A novel palladium-catalyzed hydration-olefin insertion cascade assisted by internal nucleophiles was developed for the synthesis of biologically significant 2,3-dihydro-1H-inden-1-ones under mild conditions. A detailed mechanistic study revealed that the assistance of the internal nucleophiles is crucial to trigger the cascade reaction via nucleopalladation of the alkyne moiety. The overall reaction is equivalent to regioselective hydration of alkynes followed by intramolecular Michael addition. This highly efficient and 100% atom-economical domino sequence afforded cis-2,3-disubstituted 2,3-dihydro-1H-inden-1-ones in excellent yields (up to 99%) with complete diastereoselectivity.</p>1 aVinoth, Perumal1 aNagarajan, Subbiah1 aMaheswari, Uma1 aSudalai, Arumugam1 aPace, Vittorio1 aSridharan, Vellaisamy  uhttps://library.ncl.res.in/content/palladium-catalyzed-internal-nucleophile-assisted-hydration-olefin-insertion-cascade