The lanthanide chelates of(l)-2,2-dimethyl-6-trifluoromethyl-7-oxa-6,8,8,9,9,10, 10,10-octafluoro-3,5-decanedione,Ln[(l)-CF_3CF_2CF_2OCF(CF_3)COCHCOC(CH_3)_3]_3(l-3a,Ln=Eu; 3b, Ln=Pr), are useful as ~1H NMR shift reag...The lanthanide chelates of(l)-2,2-dimethyl-6-trifluoromethyl-7-oxa-6,8,8,9,9,10, 10,10-octafluoro-3,5-decanedione,Ln[(l)-CF_3CF_2CF_2OCF(CF_3)COCHCOC(CH_3)_3]_3(l-3a,Ln=Eu; 3b, Ln=Pr), are useful as ~1H NMR shift reagents for direct determination of enantiomeric composition of enantiomorphous alcohols. ketones and amines. With these substrates. l-3a induces shift difference similar to that induced by Eu(facam)_3 and Eu(hfbc)_3. However, due to the higher solubility of the chelates l-3a and l-3b in nonpolar organic solvent such as CHCl_3, CCl_4 and only one ~1H signal from l-3a and l-3b is observed. their application as the new chiral shift reagents seems promising. The spectral nonequivalence is also observed for dimethylsulfoxide in the presence of l-3a.展开更多
文摘The lanthanide chelates of(l)-2,2-dimethyl-6-trifluoromethyl-7-oxa-6,8,8,9,9,10, 10,10-octafluoro-3,5-decanedione,Ln[(l)-CF_3CF_2CF_2OCF(CF_3)COCHCOC(CH_3)_3]_3(l-3a,Ln=Eu; 3b, Ln=Pr), are useful as ~1H NMR shift reagents for direct determination of enantiomeric composition of enantiomorphous alcohols. ketones and amines. With these substrates. l-3a induces shift difference similar to that induced by Eu(facam)_3 and Eu(hfbc)_3. However, due to the higher solubility of the chelates l-3a and l-3b in nonpolar organic solvent such as CHCl_3, CCl_4 and only one ~1H signal from l-3a and l-3b is observed. their application as the new chiral shift reagents seems promising. The spectral nonequivalence is also observed for dimethylsulfoxide in the presence of l-3a.