C. Timperley, Sally A. Saunders, Josef Szpalek
Jan 28, 2002
Citations
0
Influential Citations
18
Citations
Journal
Journal of Fluorine Chemistry
Abstract
Abstract The reactivity of bis(fluoroalkyl) phosphorochloridates to nucleophiles is summarised. Previous data and the results described here indicate that reactivities decrease in the order: amines>alcohols>thiols. The synthesis of CF 3 CH 2 OP(O)(SEt) 2 in 30% yield was accomplished by treating CF 3 CH 2 OP(O)Cl 2 with two molar equivalents of EtSH and Et 3 N in ether. The chloridates (CF 3 CH 2 O) 2 P(O)Cl and (C 2 F 5 CH 2 O) 2 P(O)Cl did not react with MeSH in ether at −78 °C or when heated with Pb(SMe) 2 in benzene. Ethanethiol and propanethiol reacted with fluorinated chloridates in the presence of triethylamine to give thiolates (R F O) 2 P(O)SR in 13–41% yield where R F was CF 3 CH 2 , C 2 F 5 CH 2 , C 3 F 7 CH 2 or (CF 3 ) 2 CH and R was Et or n -Pr. Similarly, reaction of phosphorobromidates (R F CH 2 O) 2 P(O)Br, made by brominating the corresponding bis(fluoroalkyl) H -phosphonates, with benzenethiol gave derivatives (R F CH 2 O) 2 P(O)SPh in 43 and 46% yield where R F was CF 3 and C 2 F 5 , respectively. Treatment of the chloridothiolate Cl(EtO)P(O)SMe, prepared in two steps from triethyl phosphite, with fluoroalcohols and triethylamine in ether gave species R F O(EtO)P(O)SMe in 62–74% yield where R F was CF 3 CH 2 , C 2 F 5 CH 2 , C 3 F 7 CH 2 or (CF 3 ) 2 CH. The reactions of bis(trifluoroethyl) phosphorochloridate with 2-mercaptoethanol, 3-mercaptopropanol and ethane-1,2-dithiol gave several unexpected products whose structures were tentatively assigned.