<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Tiwari, Dharmendra Kumar</style></author><author><style face="normal" font="default" size="100%">Shaikh, Ashif Y.</style></author><author><style face="normal" font="default" size="100%">Pavase, Laxmikant S.</style></author><author><style face="normal" font="default" size="100%">Gumaste, Vikas K.</style></author><author><style face="normal" font="default" size="100%">Deshmukh, Abdul Rakeeb A. S.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Stereoselective synthesis of 3-alkylidene/alkylazetidin-2-ones from azetidin-2,3-diones</style></title><secondary-title><style face="normal" font="default" size="100%">Tetrahedron</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">3-diones</style></keyword><keyword><style  face="normal" font="default" size="100%">azetidin-2</style></keyword><keyword><style  face="normal" font="default" size="100%">azetidin-2-ones</style></keyword><keyword><style  face="normal" font="default" size="100%">beta-lactam</style></keyword><keyword><style  face="normal" font="default" size="100%">Grignard reaction</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">MAR</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">11</style></number><publisher><style face="normal" font="default" size="100%">PERGAMON-ELSEVIER SCIENCE LTD</style></publisher><pub-location><style face="normal" font="default" size="100%">THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND</style></pub-location><volume><style face="normal" font="default" size="100%">63</style></volume><pages><style face="normal" font="default" size="100%">2524-2534</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Azetidin-2,3-diones have been used as synthons for the synthesis of C-3 alkylidene/alkylazetidin-2-ones. Some of the 3-alkylazetidin-2-ones are well known for their cholesterol absorption inhibitor activity. A regio and stereoselective Grignard reaction on a keto group followed by dehydration using PPh3/CCl4 reagent is a key step in this synthesis. Hydrogenation of the 3-alkylideneazetidin-2-ones provided stereoselectively cis-3-alkylazetidin-2-ones in very good yields. (c) 2006 Published by Elsevier Ltd.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">2.645</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Singh, Sanjay</style></author><author><style face="normal" font="default" size="100%">Singh, Abhijeet</style></author><author><style face="normal" font="default" size="100%">Pandya, Rinu</style></author><author><style face="normal" font="default" size="100%">Vanka, Kumar</style></author><author><style face="normal" font="default" size="100%">Singh, Ravi P.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Unlocking thermodynamic enolate for kinetically controlled desymmetrizing vinylogous (4+1) carbospiroannulation</style></title><secondary-title><style face="normal" font="default" size="100%">Chemistry-A European Journal</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">3-diones</style></keyword><keyword><style  face="normal" font="default" size="100%">alkylidene malononitrile</style></keyword><keyword><style  face="normal" font="default" size="100%">cyclopent-1</style></keyword><keyword><style  face="normal" font="default" size="100%">quaternary stereocenters</style></keyword><keyword><style  face="normal" font="default" size="100%">spiro compounds</style></keyword><keyword><style  face="normal" font="default" size="100%">thermodynamic enolate</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2025</style></year><pub-dates><date><style  face="normal" font="default" size="100%">MAY</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">31</style></volume><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;
	An unprecedented thermodynamically unfavorable (4+1) deysmmetrizing spiroannulation through a thermodynamic enolate intermediate, enabling a single-step synthesis of ubiquitous scaffolds such as all-carbon chiral spirocycles, is disclosed. In this spiroannulation, we present a vinylogous organocatalytic enantioselective desymmetrizing (4+1) cycloaddition approach involving alkylidene malononitrile and cyclopent-1,3-dienone. This carbospiroannulation method produces functionally enriched spiro[4,4]nonane structures with three stereocenters, has presented good-to-high yields and enantiomeric ratios. Detailed DFT calculations reveal an intriguing reaction mechanism, which validates our observations.&lt;/p&gt;
</style></abstract><issue><style face="normal" font="default" size="100%">27</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;
	Foreign&lt;/p&gt;
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	3.9&lt;/p&gt;
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