<?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%">Kumawat, Jugal</style></author><author><style face="normal" font="default" size="100%">Gupta, Virendra Kumar</style></author><author><style face="normal" font="default" size="100%">Vanka, Kumar</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effect of donors on the activation mechanism in ziegler-natta catalysis: a computational study</style></title><secondary-title><style face="normal" font="default" size="100%">Chemcatchem</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Alkylation</style></keyword><keyword><style  face="normal" font="default" size="100%">aluminum</style></keyword><keyword><style  face="normal" font="default" size="100%">Density functional calculations</style></keyword><keyword><style  face="normal" font="default" size="100%">surface chemistry</style></keyword><keyword><style  face="normal" font="default" size="100%">titanium</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2016</style></year><pub-dates><date><style  face="normal" font="default" size="100%">MAY</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">10</style></number><publisher><style face="normal" font="default" size="100%">WILEY-V C H VERLAG GMBH</style></publisher><pub-location><style face="normal" font="default" size="100%">POSTFACH 101161, 69451 WEINHEIM, GERMANY</style></pub-location><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">1809-1818</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Full quantum chemical calculations, using density functional theory (DFT), have been conducted to explain the effect of donors on the ``activation mechanism'' in the Ziegler-Natta (Z-N) catalyst system. In the activation mechanism, the inactive (TiCl4)-Cl-IV catalyst converts into the active (TiCl2Et)-Cl-III catalyst with the help of the AlEt3 present in the system. The donors that have been considered in this study are: ethyl benzoate (eb), two representative diether cases, a phthalate donor, and a silyl ester donor. The results indicate that eb and the diether donor cases donor have a negative effect on the barriers for the activation mechanism. However, the eb donor can be displaced from the MgCl2 surface by AlEt3, which matches experimental observations. For the phthalate, silyl ester and TiCl3-OC4H8Cl cases, the results indicate that a significant induction period would be present in Z-N systems employing such donors or having such a catalytic center, before catalysis could commence.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom3><style face="normal" font="default" size="100%">&lt;p&gt;Foreign&lt;/p&gt;</style></custom3><custom4><style face="normal" font="default" size="100%">4.724</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%">Srinivas, Kolluru</style></author><author><style face="normal" font="default" size="100%">Dangat, Yuvraj</style></author><author><style face="normal" font="default" size="100%">Kommagalla, Yadagiri</style></author><author><style face="normal" font="default" size="100%">Vanka, Kumar</style></author><author><style face="normal" font="default" size="100%">Ramana, Chepuri V.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Electronic control on linear versus branched alkylation of 2-/3-aroylbenzofurans with acrylates: combined DFT and synthetic studies</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%">acrylates</style></keyword><keyword><style  face="normal" font="default" size="100%">Alkylation</style></keyword><keyword><style  face="normal" font="default" size="100%">aroylbenzofuran</style></keyword><keyword><style  face="normal" font="default" size="100%">C-H activation</style></keyword><keyword><style  face="normal" font="default" size="100%">Density functional calculations</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2017</style></year><pub-dates><date><style  face="normal" font="default" size="100%">JUN </style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">23</style></volume><pages><style face="normal" font="default" size="100%">7570-7581</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Investigations on the factors that govern unusual branched alkylation of 2-aroylbenzofurans with acrylates by Ru-catalyzed carbonyl-directed C-H activation has been carried out by calculating the kinetics associated with the two key steps-the coordination of the acrylate with the intermediate ruthenacycle and the subsequent migratory insertion reaction-studied with the help of DFT calculations. Eight possible orientations for each mode of alkylation have been considered for the calculations. From these calculations, it has been understood that there is a synergistic operation of the steric and electronic effects favoring the branched alkylation. Further DFT investigations on the alkylation of the isomeric 3-aroylbenzofurans indicated a preference for the linear alkylation and this has been verified experimentally. Overall, the observed/calculated complementary selectivity in the alkylation of 2-/3-aroylbenzofurans with acrylates reveals that the substrate-dependent charge distribution of the Ru-C bond in the intermediate ruthenacycle is an important determining factor and thus the current work opens up a new domain of substrate design for controlling regioselectivity.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">31</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%">5.160</style></custom4></record></records></xml>