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
Previously, -(methanesulfonyl)azetidine () was found to polymerize anionically via ring-opening at temperatures >100 °C to form p(MsAzet) in the presence of an anionic initiator. In the current report, potassium(azetidin-1-ylsulfonyl) methanide (), formed from deprotonation of the methanesulfonyl group of by KHMDS, is shown to undergo spontaneous AROP at room temperature to form p(-K-MsAzet). The structure of p(-K-MsAzet) differs from that of p(MsAzet), as the sulfonyl groups are incorporated into the polymer backbone of p(-K-MsAzet). Reaction of p(-K-MsAzet) with MeOH produces p(-H-MsAzet), a semicrystalline polymer with a structure like that of polyamides, but with sulfonylamides in place of the carboxamides found in polyamides. Reaction of p(-K-MsAzet) with benzyl bromide results in the formation of amorphous p(-Bn-MsAzet). P(-K-MsAzet) is hypothesized to form via an activated monomer anionic polymerization; this is supported by polymerization kinetic data and structural characterization of the resulting polymers.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acsmacrolett.0c00019 | DOI Listing |
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!