Chemoselective Esterification and Amidation of Carboxylic Acids with Imidazole Carbamates and Ureas
摘要:
Imidazole carbamates and ureas were found to be chemoselective esterification and amidation reagents. A wide variety of carboxylic acids were converted to their ester or amide analogues by a simple synthetic procedure in high yields
The O-Acylation of Ketone Enolates by Allyl 1<i>H</i>-Imidazole-1-carboxylate Mediated with Boron Trifluoride EtherateA Convenient Procedure for the Synthesis of Substituted Allyl Enol Carbonates
作者:Barry M. Trost、Jiayi Xu
DOI:10.1021/jo7016313
日期:2007.11.1
A convenient access to substituted allylenol carbonates was established through the reaction of ketone enolates with the complex of allyl 1H-imidazole-1-carboxylates and boron trifluoride etherate.
followed by intramolecular palladium-catalyzed decarboxylative allylic alkylation. The (5)-prostaglandin E2 skeleton was also obtained from the β-keto allylic ester (11) by a similar decarboxylative allylic alkylation. The decarboxylative allylic alkylation of another type of the three-component coupling product (12) gave new 6-methyleneprostaglandin E1 skeleton (15a), which was converted into new 6-methylprosta-glandin
lopentenone by 2-alkenyloxycarbonylation of the organocopper conjugate-addition adduct followed by intramolecular palladium-catalyzed decarboxylative 2-alkenylation. A ()-2-butenylated cyclopentanone derivative was obtained from either 2-[()- or ()-2-butenyloxy-carbonyl]cyclopentanone derivative under the similar reaction condition.
Decarboxylative Allylic Alkylation of Phthalides: Stabilized Benzylic Nucleophiles for sp<sup>3</sup>–sp<sup>3</sup> Coupling
作者:Timothy J. McClure、Connor Saludares、Gisela Martinez、Cheyenne Orozco、Raul Navarro
DOI:10.1021/acs.joc.2c00723
日期:2022.6.3
A new family of stabilized benzylic nucleophiles for the palladium-catalyzed decarboxylative allylic alkylation reaction has been developed. Allyl esters derived from 3-carboxyphthalides were found to undergo palladium-catalyzed deallylation and decarboxylation under mild reaction conditions, a process facilitated by the formation of a stabilized aromatic anion. The regioselective allylic coupling
Chemoselective Esterification and Amidation of Carboxylic Acids with Imidazole Carbamates and Ureas
作者:Stephen T. Heller、Richmond Sarpong
DOI:10.1021/ol1018882
日期:2010.10.15
Imidazole carbamates and ureas were found to be chemoselective esterification and amidation reagents. A wide variety of carboxylic acids were converted to their ester or amide analogues by a simple synthetic procedure in high yields