TY - JOUR
T1 - Self-assembled superanions
T2 - Ionic capsules stabilized by polynuclear chromium(III) aqua cations
AU - Drljaca, Alexander
AU - Hardie, Michaele J.
AU - Raston, Colin L.
AU - Spiccia, Leone
PY - 1999/1/1
Y1 - 1999/1/1
N2 - Aqueous solutions of sodium p-sulfonatocalix[4]arene and 18-crown-6 containing purified, polynuclear hydrolytic CrIII cations [Cr2(OH)2(H2O)8]4+, [Cr3(OH)4(H2O)10]5+ or [Cr4(OH)6-(H2O)12]6+ (as their perchlorates) at about pH 2 afford crystalline, extensively hydrated complexes. These complexes contain the CrIII complex cations and self-assembled globularlike superanions or ionic capsules [{Na+ ⊂ (18-crown-6)-(OH2)2} ⊂ {(p-sulfonatocalix[4]arene4-)2}]7-, which are triply, doubly or singly protonated, respectively. The superanions possess a central sodium ion bound by a crown ether and two trans water molecules; this moiety is further shrouded by two calixarenes. The di-and trinuclear cations can be leached from the solid complexes by treatment with aqueous HClO4, and the complex containing the tetranuclear species is selectively formed from a solution containing a mixture of the various polynuclear cations.
AB - Aqueous solutions of sodium p-sulfonatocalix[4]arene and 18-crown-6 containing purified, polynuclear hydrolytic CrIII cations [Cr2(OH)2(H2O)8]4+, [Cr3(OH)4(H2O)10]5+ or [Cr4(OH)6-(H2O)12]6+ (as their perchlorates) at about pH 2 afford crystalline, extensively hydrated complexes. These complexes contain the CrIII complex cations and self-assembled globularlike superanions or ionic capsules [{Na+ ⊂ (18-crown-6)-(OH2)2} ⊂ {(p-sulfonatocalix[4]arene4-)2}]7-, which are triply, doubly or singly protonated, respectively. The superanions possess a central sodium ion bound by a crown ether and two trans water molecules; this moiety is further shrouded by two calixarenes. The di-and trinuclear cations can be leached from the solid complexes by treatment with aqueous HClO4, and the complex containing the tetranuclear species is selectively formed from a solution containing a mixture of the various polynuclear cations.
KW - Calixarenes
KW - Chromium
KW - Ionic capsules
KW - Polynuclear cations
KW - Self-assembly
KW - Supramolecular chemistry
UR - http://www.scopus.com/inward/record.url?scp=0032839020&partnerID=8YFLogxK
U2 - 10.1002/(SICI)1521-3765(19990802)5:8<2295::AID-CHEM2295>3.0.CO;2-O
DO - 10.1002/(SICI)1521-3765(19990802)5:8<2295::AID-CHEM2295>3.0.CO;2-O
M3 - Article
AN - SCOPUS:0032839020
VL - 5
SP - 2295
EP - 2299
JO - Chemistry-A European Journal
JF - Chemistry-A European Journal
SN - 0947-6539
IS - 8
ER -