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: 1034
Function: getPubMedXML

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3152
Function: GetPubMedArticleOutput_2016

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

Pd(II)-Catalyzed Asymmetric Annulation toward the Synthesis of 2,3-Disubstituted Chiral Indenols. | LitMetric

Pd(II)-Catalyzed Asymmetric Annulation toward the Synthesis of 2,3-Disubstituted Chiral Indenols.

J Org Chem

State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China.

Published: March 2020

An enantioselective asymmetric annulation of 2-formylboronic acids with internal alkynes has been realized using a chiral phosphinooxazoline/palladium(II) catalyst. The reaction tolerates a variety of alkynes including the relatively inert diaryl substituted internal ones. A wide range of optically active 2,3-disubstituted indenols was afforded in high yields with good to excellent enantioselectivities (up to 99% yield and 99% ee).

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.joc.9b02958DOI Listing

Publication Analysis

Top Keywords

asymmetric annulation
8
pdii-catalyzed asymmetric
4
annulation synthesis
4
synthesis 23-disubstituted
4
23-disubstituted chiral
4
chiral indenols
4
indenols enantioselective
4
enantioselective asymmetric
4
annulation 2-formylboronic
4
2-formylboronic acids
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!