A PHP Error was encountered

Severity: Warning

Message: file_get_contents(https://...@pubfacts.com&api_key=b8daa3ad693db53b1410957c26c9a51b4908&a=1): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests

Filename: helpers/my_audit_helper.php

Line Number: 176

Backtrace:

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 176
Function: file_get_contents

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 250
Function: simplexml_load_file_from_url

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3122
Function: getPubMedXML

File: /var/www/html/application/controllers/Detail.php
Line: 575
Function: pubMedSearch_Global

File: /var/www/html/application/controllers/Detail.php
Line: 489
Function: pubMedGetRelatedKeyword

File: /var/www/html/index.php
Line: 316
Function: require_once

Nickel 0-catalyzed cross-coupling of alkyl arenesulfonates with aryl Grignard reagents. | LitMetric

Nickel 0-catalyzed cross-coupling of alkyl arenesulfonates with aryl Grignard reagents.

J Org Chem

Department of Chemical Engineering, Chung-Ang University, Huksuk-Dong 221, Dongjak-Ku, Seoul 156-756, South Korea.

Published: April 2003

The nickel-catalyzed cross-coupling reactions of neopentyl arenesulfonates with arylmagnesium bromides, involving nucleophilic aromatic substitution of alkyloxysulfonyl groups by aryl nucleophiles, take place in high yields. Optimal efficiencies are obtained by adding 3 + 2 equiv of the Grignard reagent to a mixture of dppfNiCl(2) and the sulfonate in refluxing THF. Neopentyl arenesulfonates are useful sources of the electrophilic aryl groups in these transition metal-catalyzed cross-coupling reactions. Aryl sulfonates are inappropriate due to their ambident reactivity under the reaction conditions. This new cross-coupling reaction can be used for the creative elimination of alkyloxysulfonyl groups from aromatic compounds and for the preparation of unsymmetric terphenyls and oligophenyls.

Download full-text PDF

Source
http://dx.doi.org/10.1021/jo026449nDOI Listing

Publication Analysis

Top Keywords

cross-coupling reactions
8
neopentyl arenesulfonates
8
alkyloxysulfonyl groups
8
nickel 0-catalyzed
4
cross-coupling
4
0-catalyzed cross-coupling
4
cross-coupling alkyl
4
alkyl arenesulfonates
4
aryl
4
arenesulfonates aryl
4

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!