The chemistry of heteroarylphosphorus compounds. Part 11. The effects of 3-furyl and 3-thienyl substituents at phosphorus on the rate and course of alkaline hydrolysis of phosphonium salts and on the decomposition of phosphonium betaines

Author(s):  
David W. Allen ◽  
Barrie G. Hutley
1969 ◽  
Vol 22 (7) ◽  
pp. 1385 ◽  
Author(s):  
JJ Brophy ◽  
MJ Gallagher

Ethane- and ethene-1,2-bisphosphonium salts are cleaved by alkali into a phosphine and a phosphine oxide with loss of the two-carbon bridge. When the phosphorus atom carries benzyl substituents, loss of the benzyl groups is competitive with loss of the bridge. ��� Based on a kinetic study, a synchronous mechanism, analogous to the alkaline hydrolysis of acyclic monophosphonium salts, is proposed to account for the fragmentation. ��� With 6-membered 1,4-diphosphonio heterocyclic salts the nature of the products is dependent on whether alkali or phosphonium salt is present in excess. With an excess of alkali a synchronous mechanism again appears to operate, while with an excess of salt the reaction proceeds stepwise and without loss of the bridge. A partial explanation of these facts is advanced in terms of non-bonded interactions in the intermediate phosphoranes. ��� The synchronous reaction appears to be favoured by coplanarity of the P-C-C-P system.


2014 ◽  
Vol 19 (1-2) ◽  
pp. 69-77
Author(s):  
Victor S. Doroshkevich ◽  
Oksana V. Baranova ◽  
Aleksandr N. Shendrik ◽  
Aleksandr S. Doroshkevich ◽  
Olena S. Lygina ◽  
...  

Abstract Correlation between observed kinetic effects of phase-transfer catalytic reaction of the alkaline hydrolysis of 4-nitrophenyl ester of N-benzyloxycarbonylglycine-4 in the two-phase system chloroform-borate buffer pH = 10 and a content of ionic forms of catalyst was investigated. The phosphonium salts QX (X = Cl¯, Br¯, I¯) shows high catalytic reactivity. Dependence of the reaction kinetics discussed in the framework of the extraction mechanism with a competitive extraction of a nucleophile ОН¯, nucleofuge 4-NO2C6H4O¯ and anion X¯ of the phase-transfer catalyst.


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