ISSN:
0021-8383
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Organophosphorus Antioxidants. III. Kinetics and Mechanism of the Decomposition of Cumyl Hydroperoxide by Cyclic PhosphitesThe reaction mechanism of cyclic esters of phosphorous acids I to VIII with cumyl hydroperoxide has been studied kinetically by means of 31P n.m.r. spectroscopy, high performance liquid chromatography and iodometric titration.The five-membered cyclic phosphites (I and II) react with cumyl hydroperoxide to give the corresponding phosphates (AI and AII) and cumyl alcohol. With more hydroperoxide or water they form the open chain phosphate esters (BI and BII) which decompose cumyl hydroperoxide catalytically giving phenol and acetone. Higher membered cyclic phosphites (III to VIII) react with cumyl hydroperoxide to give the corresponding phosphates and alcohol only. The mode of reaction depends on the hydrolysis behaviour of the cyclic phosphates (AI to A VIII). Only fivemembered cyclic phosphites which give easily hydrolyzable phosphates are able to decompose cumyl hydroperoxide catalytically. The nature of the exocyclic group in the phosphites has no influence on this behaviour.The kinetic parameters of the separate reaction steps are given.The ionic mechanism of hydroperoxide decomposition is accompanied by a homolytic one.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/prac.19843260415
