01240nas a2200217   4500008004100000022001400041245010800055210006900163260010600232300001400338490000700352520037500359653001100734653002400745653003000769653001700799100002200816700002600838700002700864856013100891       2006                        eng d  a0040-403900aGamma-heteroatom directed stereocontrolled staudinger cycloaddition reaction of vinylketenes and imines0 aGammaheteroatom directed stereocontrolled staudinger cycloadditi  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcAUG  a5993-59960 v473 a<p>Vinylketenes possessing a gamma-heteroatom, on Staudinger cycloaddition reaction with imines gave trans-3-vinyl-beta-lactams in very good yields. The vinyl side chain stereoselectively adopts the Z-configuration in the transition state to stabilize the vinylketene and produces, exclusively, trans-3-vinyl-beta-lactams. (c) 2006 Elsevier Ltd. All rights reserved.</p>10aimines10aStaudinger reaction10astereoselective synthesis10avinylketenes1 aShaikh, Aarif, L.1 aPuranik, Vedavati, G.1 aDeshmukh, A., R. A. S.  uhttps://library.ncl.res.in/content/gamma-heteroatom-directed-stereocontrolled-staudinger-cycloaddition-reaction-vinylketenes-001434nas a2200229   4500008004100000022001400041245014500055210006900200260010600269300001400375490000700389520050600396653001100902653001200913653002300925653002400948653003000972100002701002700002601029700002701055856012201082       2007                        eng d  a0040-402000aStereoselective synthesis of spiro-beta-lactams using D-(+)-glucose derived chiral pool: remarkable influence of the torquoelectronic effect0 aStereoselective synthesis of spirobetalactams using Dglucose der  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcSEP  a9179-91870 v633 a<p>Diastereoselective synthesis of spiro-beta-lactams via [2+2] cycloaddition reaction of imines and chiral ketenes is described. The chiral ketene was prepared from commercially available, inexpensive D-glucose. Although, theoretically four diastereomers are possible, the reaction yielded only two diastereomers stereoselectively in good to moderate yields. The stereochemical outcome of the reaction was in accordance with the torquoelectronic model. (c) 2007 Elsevier Ltd. All rights reserved.</p>10aimines10aketenes10aspiro-beta-lactams10aStaudinger reaction10astereoselective synthesis1 aChincholkar, Pinak, M.1 aPuranik, Vedavati, G.1 aDeshmukh, A., R. A. S.  uhttps://library.ncl.res.in/content/stereoselective-synthesis-spiro-beta-lactams-using-d-glucose-derived-chiral-pool-0