01302nas a2200205   4500008004100000022001400041245013700055210006900192260011000261300001600371490000700387520043100394100002300825700003300848700001700881700002200898700002400920700002200944856013000966       2014                        eng d  a1359-734500aN-Heterocyclic carbene-catalyzed enantioselective synthesis of functionalized cyclopentenes via alpha,beta-unsaturated acyl azoliums0 aNHeterocyclic carbenecatalyzed enantioselective synthesis of fun  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcOCT  a14539-145420 v503 a<p>Highly enantioselective NHC-organocatalyzed synthesis of functionalized cyclopentenes proceeding via alpha,beta-unsaturated acyl azolium intermediates is reported. The organocascade reaction of modified enals with malonic ester derivatives having a gamma-benzoyl group involves the Michael-intramolecular aldol-beta-lactonization-decarboxylation sequence to deliver cyclopentenes in good yields and excellent ee values.</p>1 aMondal, Santigopal1 aYetra, Santhivardhana, Reddy1 aPatra, Atanu1 aKunte, Sunita, S.1 aGonnade, Rajesh, G.1 aBiju, Akkattu, T.  uhttps://library.ncl.res.in/content/n-heterocyclic-carbene-catalyzed-enantioselective-synthesis-functionalized-cyclopentenes-001234nas a2200181   4500008004100000245013800041210007000179260000800249300001400257490000700271520052900278100002300807700002300830700001700853700002400870700002200894856013600916       2015                        eng d00aN-Heterocyclic carbene-catalyzed diastereoselective synthesis of β-lactone-fused cyclopentanes using homoenolate annulation reaction0 aNHeterocyclic carbenecatalyzed diastereoselective synthesis of β  cMAY  a9559-95620 v513 a<p><span style="font-family: Arial;">NHC-catalyzed annulation of enals with 2-enoylpyridines or 2-enoylpyridine&nbsp;</span><em style="font-family: Arial;">N</em><span style="font-family: Arial;">-oxides leading to the diastereoselective synthesis of β-lactone-fused cyclopentanes is reported. The reaction proceeds&nbsp;</span><em style="font-family: Arial;">via</em><span style="font-family: Arial;">&nbsp;the generation of homoenolate equivalent intermediates and tolerates a broad range of functional groups.</span></p>1 aMukherjee, Subrata1 aMondal, Santigopal1 aPatra, Atanu1 aGonnade, Rajesh, G.1 aBiju, Akkattu, T.  uhttps://library.ncl.res.in/content/n-heterocyclic-carbene-catalyzed-diastereoselective-synthesis-%CE%B2-lactone-fused-cyclopentanes01531nas a2200265   4500008004100000022001400041245010100055210006900156260000800225300001400233490000600247520065000253653002400903653001800927653001900945653001400964653002800978653002001006100002301026700002301049700002201072700002001094700002201114856012901136       2017                        eng d  a2155-543500aN-Heterocyclic carbene-catalyzed aldol-lactonization of ketoacids via dynamic kinetic resolution0 aNHeterocyclic carbenecatalyzed aldollactonization of ketoacids v  cJUN  a3995-39990 v73 a<p>N-Heteroryclic carbene (NHC)-catalyzed enantioselective aldol lactonization of acyclic ketoacids, proceeding via dynamic kinetic resolution, is presented. The carbene generated from the chiral anninoinclanol-derived triazolium salt in the presence of LiCl was the key for the success of this transformation. The reaction allowed the diastereoselective and enantioselective synthesis of cyclopentane-fused beta-lactones having three contiguous stereocenters. The reaction products are shown to undergo substrate-controlled beta-lactone opening in the presence of amines to afford succinimide derivatives with four contiguous stereocenters.</p>10aaldol lactonization10abeta-lactones10aDKR strategies10aketoacids10aN-heterocyclic carbenes10aorganocatalysis1 aMondal, Santigopal1 aMukherjee, Subrata1 aDas, Tamal, Kanti1 aGonnade, Rajesh1 aBiju, Akkattu, T.  uhttps://library.ncl.res.in/content/n-heterocyclic-carbene-catalyzed-aldol-lactonization-ketoacids-dynamic-kinetic-resolution01194nas a2200181   4500008004100000022001400041245012600055210006900181260000800250300001400258490000700272520051900279100002300798700001800821700002300839700002200862856012800884       2018                        eng d  a1523-706000aN-Heterocyclic carbene-catalyzed enantioselective synthesis of spiro-glutarimides via alpha,beta-unsaturated acylazoliums0 aNHeterocyclic carbenecatalyzed enantioselective synthesis of spi  cAUG  a4499-45030 v203 a<p>NHC-catalyzed enantioselective [3 + 3] spiro-annulation of alpha,beta-unsaturated aldehydes with cyclic beta-ketoamides allowing the preparation of synthetically and biologically important spiro-glutarimide derivatives has been reported. The interception of the ketoamides with catalytically generated chiral alpha,beta-unsaturated acylazoliums proceeds in a Michael addition-intramolecular amidation pathway to deliver the spirocyclic products with good yield, diastereoselectivity, and enantioselectivity.</p>1 aMondal, Santigopal1 aGhosh, Arghya1 aMukherjee, Subrata1 aBiju, Akkattu, T.  uhttps://library.ncl.res.in/content/n-heterocyclic-carbene-catalyzed-enantioselective-synthesis-spiro-glutarimides-alphabeta01427nas a2200145   4500008004100000022003100041245007600072210006900148260001000217520086800227100002301095700003001118700002201148856011101170       2019                        eng d  aOnline ISBN: 978352780904200aN-heterocyclic carbene-catalyzed stetter reaction and related chemistry0 aNheterocyclic carbenecatalyzed stetter reaction and related chem  bWiley3 aThe reversal of normal mode of reactivity (umpolung) of aldehydes is the most important application of N-heterocyclic carbenes (NHCs) in organocatalytic transformations. The benzoin condensation and the Stetter reaction are the two historic reactions where NHC reacts with aldehyde to generate acyl anion equivalent, which is subsequently intercepted with another molecule of carbonyl compound or Michael acceptor leading to the formation of the benzoin/Stetter products. The objective of this chapter is to provide an overview on NHC-catalyzed Stetter reaction and related chemistry. The development of various chiral catalysts for enantioselective intra- or intermolecular Stetter reaction has been described. Additionally, recent progress on NHC-catalyzed addition of aldehyde to unactivated multiple bonds in the hydroacylation reaction has been demonstrated.1 aMondal, Santigopal1 aYetra, Santhivardhana, R.1 aBiju, Akkattu, T.  uhttps://library.ncl.res.in/content/n-heterocyclic-carbene-catalyzed-stetter-reaction-and-related-chemistry