01209nas a2200181 4500008004100000022001400041245013600055210006900191260007100260300001400331490000700345520045900352100002000811700002400831700002500855700002200880856012500902 2013 eng d a0022-326300aCuCN-Mediated cascade cyclization of 4-(2-bromophenyl)-2-butenoates: a high-yield synthesis of substituted naphthalene amino esters0 aCuCNMediated cascade cyclization of 42bromophenyl2butenoates a h a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcMAY a5045-50500 v783 a

A new method of CuCN-mediated one-pot cyclization of 4-(2-bromophenyl)-2-butenoates leading to efficient synthesis of substituted naphthalene amino esters including phenanthrene aromatic structural units is described. Deuterium labeling studies establish that this one-pot cascade cyclization proceeds through isomerization of olefin, intramolecular C-C bond cyclization, and aromatization as the key intermediates, all occurring in a single step.

1 aReddy, Santhosh1 aPrasad, Pragati, K.1 aAhuja, Brij, Bhushan1 aSudalai, Arumugam uhttps://library.ncl.res.in/content/cucn-mediated-cascade-cyclization-4-2-bromophenyl-2-butenoates-high-yield-synthesis-001128nas a2200157 4500008004100000022001400041245018900055210006900244260000900313300001000322490000700332520045700339100002500796700002200821856012700843 2015 eng d a0957-416600aConcise enantioselective synthesis of (2S,3S)-3-hydroxypipecolic acid via proline catalyzed alpha-aminooxylation of aldehydes and Pd-catalyzed ether directed aza-Claisen rearrangements0 aConcise enantioselective synthesis of 2S3S3hydroxypipecolic acid cJAN  a24-280 v263 a

An efficient approach to (2S,3S)-3-hydroxypipecolic acid with an overall yield of 10.2% and 98% ee starting from 1,5-pentanediol has been developed. The key steps employed in the synthesis are the D-proline catalyzed sequential alpha-aminooxylation/Horner-Wadsworth-Emmons olefination of an aldehyde and the Pd-catalyzed MOM-ether directed aza-Claisen rearrangement of an allylic trichloroacetimidate. (C) 2014 Elsevier Ltd. All rights reserved.

1 aAhuja, Brij, Bhushan1 aSudalai, Arumugam uhttps://library.ncl.res.in/content/concise-enantioselective-synthesis-2s3s-3-hydroxypipecolic-acid-proline-catalyzed-alpha01189nas a2200157 4500008004100000022001400041245011500055210006900170260011000239300001400349490000700363520049300370100002500863700002200888856012100910 2015 eng d a1477-052000aCu-catalyzed debrominative cyanation of gem-dibromoolefins: a facile access to alpha,beta-unsaturated nitriles0 aCucatalyzed debrominative cyanation of gemdibromoolefins a facil aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcAPR a5918-59230 v133 a

An efficient catalytic route for the synthesis of alpha,beta-unsaturated nitriles from easily accessible gem-dibromoolefins has been developed. The method utilized inexpensive reagents such as Cu2O as a catalyst, L-proline as a ligand and NaCN as a cyanide source to afford alpha,beta-unsaturated nitriles in high yields (62-86%). A deuterium exchange study has shown that one of the bromide atoms of gem-dibromoolefins exchanges with cyanide while the other with a deuterium atom.

1 aAhuja, Brij, Bhushan1 aSudalai, Arumugam uhttps://library.ncl.res.in/content/cu-catalyzed-debrominative-cyanation-gem-dibromoolefins-facile-access-alphabeta-001284nas a2200157 4500008004100000022001400041245018200055210006900237260010600306300001200412490000700424520052400431100002500955700002200980856012401002 2015 eng d a0957-416600aFirst enantioselective synthesis of (2S,3S)-3-hydroxy-L-arginine via proline catalyzed alpha-aminooxylation of aldehyde and Pd-catalyzed ether-directed aza-Claisen rearrangement0 aFirst enantioselective synthesis of 2S3S3hydroxyLarginine via pr aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcMAY a548-5520 v263 a

A concise enantioselective synthesis of (2S,3S)-3-hydroxy-L-arginine with an overall yield of 10.9% and 98% ee, starting from commercially available 1,4-butanediol in ten linear steps has been achieved. The key chiral inducing steps are D-proline catalyzed sequential alpha-aminooxylation/Horner-Wadsworth-Emmons olefination of an aldehyde and the subsequent diastereoselective MOM-ether-directed Pd-catalyzed aza-Claisen rearrangement of allylic trichloroacetimidate. (C) 2015 Elsevier Ltd. All rights reserved.

1 aAhuja, Brij, Bhushan1 aSudalai, Arumugam uhttps://library.ncl.res.in/content/first-enantioselective-synthesis-2s3s-3-hydroxy-l-arginine-proline-catalyzed-alpha-001267nas a2200157 4500008004100000022001400041245018300055210006900238260011000307300001600417490000600433520049200439100002500931700002200956856013100978 2015 eng d a2046-206900aOne-pot highly enantio- and diastereoselective synthesis of anti,anti vinylic 3-amino-1,2 diols via proline catalyzed sequential alpha-amination/benzoyloxyallylation of aldehydes0 aOnepot highly enantio and diastereoselective synthesis of antian aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcFEB a21803-218050 v53 a

The first direct asymmetric synthesis of anti, anti vinylic 3-amino-1,2-diols from aldehydes is described via a one-pot sequential L-proline catalyzed alpha-amination/benzoyloxyallylation protocol. The reaction proceeds with exceptionally high diastereoselectivity (>99%) as can be explained based on the Felkin-Ahn transition state model. Its effectiveness is proven unambiguously by demonstrating a short asymmetric synthesis of D-ribo-phytosphingosine tetraacetate (93% ee).

1 aAhuja, Brij, Bhushan1 aSudalai, Arumugam uhttps://library.ncl.res.in/content/one-pot-highly-enantio-and-diastereoselective-synthesis-antianti-vinylic-3-amino-12-diols-001437nas a2200229 4500008004100000022001400041245017700055210006900232260007500301300001400376490000700390520052700397653001400924653002300938653002000961653001200981653001800993100002501011700002601036700002201062856012301084 2016 eng d a0936-521400aFormal enantioselective synthesis of (-)-epiquinamide by proline-catalyzed one-pot sequential -amination/propargylation of aldehyde and asymmetric dihydroxylation of olefin0 aFormal enantioselective synthesis of epiquinamide by prolinecata aRUDIGERSTR 14, D-70469 STUTTGART, GERMANYbGEORG THIEME VERLAG KGcJUL a1699-17020 v273 a

Two independent routes to the formal synthesis of (-)-epiquinamide, have been described: the first route utilizes an l-proline-catalyzed one-pot sequential -amination/propargylation of aldehyde, while the second one employs asymmetric dihydroxylation as the key reaction to install the stereochemistry. While the first synthesis was accomplished in nine steps with 24.4% overall yield and dr 9:1, the second strategy resulted in the synthesis in eight steps with 36.4% overall yield and with perfect enantiocontrol.

10aAmination10adiastereoselective10aDihydroxylation10aProline10aquinolizidine1 aAhuja, Brij, Bhushan1 aEmmanuvel, Lourdusamy1 aSudalai, Arumugam uhttps://library.ncl.res.in/content/formal-enantioselective-synthesis-epiquinamide-proline-catalyzed-one-pot-sequential01490nas a2200253 4500008004100000022001400041245017700055210006900232260010600301300001200407490000700419520047900426653001800905653002700923653001400950653000900964653002300973100001600996700002301012700002501035700002301060700002201083856013101105 2016 eng d a0040-403900aPd-catalyzed reductive cleavage of N-N bond in dibenzyl-1-alkylhydrazine-1,2-dicarboxylates with PMHS: application to a formal enantioselective synthesis of (R)-sitagliptin0 aPdcatalyzed reductive cleavage of NN bond in dibenzyl1alkylhydra aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcFEB a684-6870 v573 a

An environmentally benign approach involving Pd-catalyzed reductive N-N bond cleavage in dibenzyl-1-alkylhydrazine-1,2-dicarboxylates leading to the synthesis of N-(tert-butoxy)carbamates under very mild conditions has been described. PMHS serves as an inexpensive source of hydride in MeOH/deionized H2O medium. This protocol has been successfully applied in the formal synthesis of (R)-sitagliptin, an anti-diabetic drug. (C) 2015 Elsevier Ltd. All rights reserved.

10aanti-Diabetic10aEnvironmentally benign10aHydrazine10aPMHS10aReductive cleavage1 aDey, Soumen1 aGadakh, Sunita, K.1 aAhuja, Brij, Bhushan1 aKamble, Sanjay, P.1 aSudalai, Arumugam uhttps://library.ncl.res.in/content/pd-catalyzed-reductive-cleavage-n-n-bond-dibenzyl-1-alkylhydrazine-12-dicarboxylates-pmhs-003259nas a2200145 4500008004100000245015100041210007000192260001800262300001200280490000700292520263000299100002502929700002202954856013702976 2020 eng d00aOrganocatalyzed α-aminooxylation/amination of aldehydes and their sequential reactions: a versatile tool for the synthesis of bioactive molecules0 aOrganocatalyzed αaminooxylationamination of aldehydes and their  bElsevier B.V. a417-4650 v643 a

This chapter introduces the sequential reactions of proline catalyzed α-aminooxylation and α-amination of aldehydes and its broad applications in the synthesis of bioactive molecules. It starts by presenting an overview of organocatalysis, particularly proline and its catalytic behavior. It then explains the proline catalyzed α-aminooxylation reaction and its sequential reactions one by one along with its applications in the synthesis of natural products. Next, it describes the l- and d-proline catalyzed α-amination and its sequential reactions. A full description of the synthetic scheme of natural products is provided.

1 aAhuja, Brij, Bhushan1 aSudalai, Arumugum uhttps://library.ncl.res.in/content/organocatalyzed-%CE%B1-aminooxylationamination-aldehydes-and-their-sequential-reactions-versatile