Severity: Warning
Message: file_get_contents(https://...@gmail.com&api_key=61f08fa0b96a73de8c900d749fcb997acc09): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests
Filename: helpers/my_audit_helper.php
Line Number: 143
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 143
Function: file_get_contents
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 209
Function: simplexml_load_file_from_url
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3098
Function: getPubMedXML
File: /var/www/html/application/controllers/Detail.php
Line: 574
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 488
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Attempt to read property "Count" on bool
Filename: helpers/my_audit_helper.php
Line Number: 3100
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3100
Function: _error_handler
File: /var/www/html/application/controllers/Detail.php
Line: 574
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 488
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 316
Function: require_once
m-Terphenyl- and biphenyl-2-diiodophosphines, TerphPI 2 and BiphPI 2, have been obtained by halide exchange from the chloro derivatives TerphPCl 2 and BiphPCl 2 and excess LiI in a benzene solution at room temperature. Whereas BiphPI 2 compounds are stable, the TerphPI 2 species undergo intramolecular C-H activation at room temperature and cyclize to form unsymmetrical 9-iodo-9-phosphafluorenes 1-(3,5-dimethylphenyl)-6,8-dimethyl-9-iodo-9-phosphafluorene, 4; 1-(4-t-butylphenyl)-7-t-butyl-9-iodo-9-phosphafluorene, 5; and 1-(2-methylphenyl)-5-methyl-9-iodo-9-phosphafluorene, 6, albeit the latter reaction is rather slow due to unfavorable steric interactions. Cyclization of the alkyl-substituted 4,4'-di- tert-butyl-biphenyl-2-diiodophosphine, 11, is slow in refluxing benzene solution, but faster than that for the parent biphenyl-2-diiodophosphine. Ab initio and density functional theory calculations are in agreement with an electrophilic aromatic substitution mechanism that is facilitated by steric strains in the terphenyl compounds 2,6-(3,5-Me2C6H3)2C6H3PI2, 1; 2,6-(4-t-BuC6H4)2C6H3PI 2, 2; and 2,6-(2-MeC6H4)2C6H3PI 2, 3. All new compounds have been characterized by multinuclear NMR spectroscopy and direct analysis in real time mass spectrometry. 9-Iodo-9-phosphafluorene, 12, was also analyzed by X-ray diffraction.
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http://dx.doi.org/10.1021/ic702105s | DOI Listing |
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