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
A series of S 1-type reactions has been studied under various conditions to clarify the role of supercritical carbon dioxide (scCO ) as reaction medium for this kind of transformations. The application of scCO did not result in higher yields in any of the experiments in comparison to those under neat conditions or in the presence of other inert compressed gases. High-pressure UV/Vis spectroscopic measurements were carried out to quantify the degree of carbocation formation of a highly S 1-active alkyl halide as a function of the applied solvent. No measureable concentration of carbocations could be detected in scCO , just like in other low polarity solvents. Taken together, these results do not support the previously claimed activating effect via enhanced S 1 ionization due to the quadrupolar moment of the supercritical fluid.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/chem.201604151 | DOI Listing |
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!