231610-97-2Relevant academic research and scientific papers
Intramolecular nucleophilic displacement of halogen by phosphinate and thiophosphinate anions: Relative rates of formation of five- And six-membered rings 1
Chaudhry, Amirah,Hargcr, Martin J. P.,Shuff, Philippa,Thompson, Alison
, p. 1347 - 1352 (2007/10/03)
Intramolecular nucleophilic substitution transforms the phosphinate anions XCH2CH2(CH2)nCH2(Ph)P(O)O (n = 0, 1; X = Br, Cl) (Et3NH+ salts; CH2Cl2 solution) into cyclic phosphinate esters 14 (n - 0,1); unusually the five-membered ring product (n = 0) is formed only 4.3 (X = Br) or 5.7 (X = Cl) times faster than the six (n = 1). The analogous cyclisation of the thiophosphinate anions ClCH2CH2(CH2)nCH 2(Ph)P(S)CT (n = 0,1) gives the products 16 (n = 0, 1) with the sulfur atom in the ring; the five-membered ring is now formed 30 times faster than the six, still a rather modest rate advantage.
