<?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%">Mukherjee, Subrata</style></author><author><style face="normal" font="default" size="100%">Joseph, Sumi</style></author><author><style face="normal" font="default" size="100%">Bhunia, Anup</style></author><author><style face="normal" font="default" size="100%">Gonnade, Rajesh Ghanshyam</style></author><author><style face="normal" font="default" size="100%">Reddy, Santhi Vardhan</style></author><author><style face="normal" font="default" size="100%">Biju, Akkattu T.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Enantioselective synthesis of spiro γ-butyrolactones by N-heterocyclic carbene (NHC)-catalyzed formal [3+2] annulation of enals with 3-hydroxy oxindoles</style></title><secondary-title><style face="normal" font="default" size="100%">Organic &amp; Biomolecular Chemistry </style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2017</style></year><pub-dates><date><style  face="normal" font="default" size="100%">FEB</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">16</style></volume><pages><style face="normal" font="default" size="100%">2013 - 2019</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The N-heterocyclic carbene (NHC)-catalyzed enantioselective formal [3 + 2] annulation of α,β-unsaturated aldehydes with 3-hydroxy oxindoles is presented. Under oxidative conditions using the bisquinone oxidant, the reaction resulted in the synthesis of spiro γ-butyrolactones in moderate to good yields, enantioselectivity and diastereoselectivity. The reaction likely proceeds via the generation of the NHC-bound α,β-unsaturated acylazolium intermediate from enals, which was intercepted by the dioxindoles in a formal [3 + 2] pathway to form the spirocyclic compounds. However, a deeper mechanistic investigation revealed that the reaction can also proceed via the homoenolate intermediate. In this case, the dioxindole was oxidized to the corresponding isatin derivative using traces of air under basic conditions, and was intercepted with the NHC-bound homoenolate intermediate in a formal [3 + 2] pathway to afford the spiro compound.</style></abstract><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">3.559</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%">Madhu, Suresh</style></author><author><style face="normal" font="default" size="100%">Rashmi, E. V.</style></author><author><style face="normal" font="default" size="100%">Gonnade, Rajesh Ghanshyam</style></author><author><style face="normal" font="default" size="100%">Sanjayan, Gangadhar J.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Exploring the gem-dimethyl effect in the formation of imine-based macrocycles and cages</style></title><secondary-title><style face="normal" font="default" size="100%">New Journal of Chemistry</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2017</style></year><pub-dates><date><style  face="normal" font="default" size="100%">JUL</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">17</style></volume><pages><style face="normal" font="default" size="100%">8721-8724 </style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Using the gem-dimethyl effect as a platform, a variety of organic [2+2] macrocycles and [2+3] cofacial cages was obtained in high yields. Imine-based macrocyclization could be performed even at high concentrations (0.5 to 1.0 M), via instant mixing of aldehydes and amines.</style></abstract><issue><style face="normal" font="default" size="100%">41</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%">3.269</style></custom4></record></records></xml>