Synthesis of Phospholane 1-Oxide Having Oxygen Functional Groups from a 4-Bromobutylphoshinate Derivative
摘要:
Ethyl 4-bromo-2,3-dimethoxybutyl(phenyl)phosphinate (10a) was prepared from 2,3-di-0-methyl-L-threitol (12) in five steps. Reduction of 10a with sodium dihydrobis(2-methoxyethoxy)aluminate, followed by the action of hydrogen peroxide, afforded 3,4-dimethoxy-1-phenylphospholane I-oxide (3), while the reaction of 10a with magnesium in boiling THF resulted in the formation of ethyl 2-methoxy-3-butenyl(phenyl)phosphinate (26).
Intramolecular nucleophilic displacement of halogen by phosphinate and thiophosphinate anions: relative rates of formation of five- and six-membered rings 1
作者:Amirah Chaudhry、Martin J. P. Harger、Philippa Shuff、Alison Thompson
DOI:10.1039/a900623k
日期:——
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)nCH2(Ph)P(S)O–
Intramolecular nucleophilic substitution by phosphinate and thiophosphinate anions: relative rates of formation of five- and six-membered rings
作者:Amirah Chaudhry、Martin J. P. Harger、Philippa Shuff、Alison Thompson
DOI:10.1039/c39950000083
日期:——
In CH2Cl2 solution the phosphinate anion BrCH2CH2(CH2)nCH2(Ph)P(O)O– cyclises only 4,3 times faster when n= 0 (five-membered ring product) than when n= 1; for the thiophosphinate anion ClCH2CH2(CH2)nCH2(Ph)P(S)O– cyclisation (via sulfur) is still only 30 times faster when n= 0 than when n= 1.