Kinetic Study of the Phenolysis of <i>O</i>-Methyl and <i>O</i>-Phenyl <i>O</i>-2,4-Dinitrophenyl Thiocarbonates and <i>O</i>-Ethyl 2,4-Dinitrophenyl Dithiocarbonate
作者:Enrique A. Castro、David Arellano、Paulina Pavez、José G. Santos
DOI:10.1021/jo034538+
日期:2003.8.1
(PDNPTOC), and O-ethyl2,4-dinitrophenyldithiocarbonate (EDNPDTC) are studied kinetically in water, at 25.0 degrees C and an ionic strength of 0.2 M (KCl). All reactions show pseudo-first-order kinetics under an excess of phenol over the substrate, and are first order in phenoxide anion. The reactions of EDNPDTC show a linear Bronsted-type plot of slope beta = 0.67, suggesting a concerted mechanism. On the
Radical 1,2-O→C Transposition for Conversion of Phenols into Benzoates by O-Neophyl Rearrangement/Fragmentation Cascade
作者:Abdulkader Baroudi、Jeremiah Alicea、Igor V. Alabugin
DOI:10.1002/chem.201001056
日期:——
Radical merry‐go‐round! Diaryl thiocarbonates, available in a single step from phenols, can be directly transformed into benzoates by a new radicalcascade that transposes O and C atoms at the aromatic core. The cascade bypasses the common Barton–McCombie fragmentation in favor of the usually unfavorable O‐neophyl rearrangement, which is rendered irreversible and efficient by a highly exothermic CS
DIRECT CONVERSION OF PHENOLS INTO AMIDES AND ESTERS OF BENZOIC ACID
申请人:Alabugin Igor
公开号:US20110237798A1
公开(公告)日:2011-09-29
A method is provided for the preparation of an aromatic carboxylic acid aryl ester or an N-aryl aromatic carboxamide. The method comprises contacting an O,O-diaryl thiocarbonate or an O-aryl-N-aryl thiocarbamate with a reactant that regioselectively reacts with sulfur, which contact causes an O-neophyl rearrangement, thereby forming either the aromatic carboxylic acid aryl ester or the N-aryl aromatic carboxamide, respectively.
Kinetic and theoretical study on nucleofugality in the phenolysis of 3-nitrophenyl and 4-nitrophenyl 4-cyanophenyl thionocarbonates
作者:Enrique A. Castro、Alvaro Cañete、Paola R. Campodónico、Marjorie Cepeda、Paulina Pavez、Renato Contreras、José G. Santos
DOI:10.1016/j.cplett.2013.04.002
日期:2013.5
evaluate the nucleofugality of the corresponding leavinggroups. For the reaction of 2 only 4-nitrophenoxide is obtained as leavinggroup. For the reaction of 1 the nucleofugality ratio 3-nitrophenoxide/4-cyanophenoxide is 1/3 from the corresponding T− intermediate. Theoretical calculations confirm the experimental results. From these results it can be concluded that the non-leaving group affects the