02098nas a2200205   4500008004100000022001400041245011100055210006900166260007100235300001600306490000800322520129100330100002801621700001801649700002101667700002501688700002501713700002901738856012501767       2013                        eng d  a1932-744700aSpin transport and magnetic correlation parameters for graphene-like nanocarbon sheets doped with nitrogen0 aSpin transport and magnetic correlation parameters for graphenel  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcDEC  a27105-271130 v1173 a<p>Globally, graphene magnetism has captivated the attention of researchers in recent years. To obtain magnetic ordering, irregularities in the carbon network, like defects, adatoms, etc., are essential. Herein, we report on spin transport and magnetic correlations in graphene-like nanocarbon sheets (GNCs) that were doped with nitrogen by use of tetrakis(dimethylamino)ethylene (TDAE). The spin transport measurements, performed by electron spin resonance technique, showed that both spin-spin and spin-lattice relaxation times are increased by nitrogen doping. The magnetic correlations, measured on a vibrating sample magnetometer, showed that ordering parameters are reduced for nitrogen-loaded GNCs. Chemical analysis, carried out via electron spectroscopy, revealed that nitrogen atoms exchange couples electron-to-hole with the carbon network Analysis of I-V measurements showed that higher-order resistance is appreciably decreased for nitrogen-doped GNCs. The observed decrease is due to an increase in nonbonding states baying small local density. After doping, states in this region may be localized pi spin populated around the doped region. By and large, the approximately 20% magnetization that exists in GNCs is found to be reduced to 5% by introduction of nitrogen.</p>1 aAlegaonkar, Ashwini, P.1 aKumar, Arvind1 aPatil, Sagar, H.1 aPatil, Kashinath, R.1 aPardeshi, Satish, K.1 aAlegaonkar, Prashant, S.  uhttps://library.ncl.res.in/content/spin-transport-and-magnetic-correlation-parameters-graphene-nanocarbon-sheets-doped-001834nas a2200253   4500008004100000022001400041245015100055210006900206260007700275300001400352520086900366653002001235653002501255653001301280653002401293100001901317700001801336700001801354700001601372700001701388700002401405700002301429856012801452       2014                        eng d  a1434-193X00aSynthesis of alpha,beta-unsaturated delta-lactones by vinyl acetate mediated asymmetric cross-aldol reaction of acetaldehyde: mechanistic insights0 aSynthesis of alphabetaunsaturated deltalactones by vinyl acetate  aBOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANYbWILEY-V C H VERLAG GMBHcAUG  a5247-52553 a<p>A tandem asymmetric cross-aldol reaction involving the in situ generation of acetaldehyde from vinyl acetate has been developed that may resolve the challenges associated with the handling of acetaldehyde. The simple protocol, mild reaction conditions and unique harmony of an organocatalyst with a biocatalyst make this method a valuable tool for the synthesis of asymmetric beta-hydroxy aldehydes. By using this methodology we have accessed alpha,beta-unstaurated delta-lactones as well as isochromenones with high enantioselectivities from both asymmetric beta-hydroxy aldehydes and ketones. Systemic density functional theory (DFT) studies were also performed to gain mechanistic insights into the role of hydrogen bonding in the asymmetric cross-aldol reaction of acetaldehyde and in the key cis/trans isomerisation step in the synthesis of d-lactones.</p>10aAldol reactions10aasymmetric catalysis10alactones10areaction mechanisms1 aKumar, Manjeet1 aKumar, Arvind1 aRizvi, Masood1 aMane, Manoj1 aVanka, Kumar1 aTaneja, Subhash, C.1 aShah, Bhahwal, Ali  uhttps://library.ncl.res.in/content/synthesis-alphabeta-unsaturated-delta-lactones-vinyl-acetate-mediated-asymmetric-cross-0