TY - JOUR
T1 - Organization of Lower Rim O-Alkylated p-Phosphonic Acid Calix[4]arenes
AU - Clark, Thomas
AU - Makha, Mohamed
AU - Sobolev, Alexandre
AU - Su, D.
AU - Rohrs, H.
AU - Gross, M.L.
AU - Raston, Colin
PY - 2009
Y1 - 2009
N2 - Lower rim O-methyl, -n-butyl, and n-octadecyl calix[4]arenes bearing p-phosphonic acid groups on the upper rim have been prepared in high yield, compounds 12−14. Where possible, the compounds have been characterized in the solid state using X-ray diffraction, or as the precursor phosphate esters or a cesium salt. The cone conformation ethyl phosphate ester for the octadecyl compound crystallizes in a bilayer 39.1 Å thick, which approaches the 40 Å of biological membranes. The 1,3-alternate cone conformation of the cesium salt of the O-methyl phosphonic acid has a metal ion coordinated to two methoxy groups, four O−P (two from neighboring calixarenes), and two η3-C3 moieties from two 1,3-disposed aromatic rings. MALDI-TOF spectra of compounds 12−14 show successive peaks corresponding to 15, 33, and 16 calixarene units, which is consistent with the intramolecular H-bonding capabilities of the diprotic phosphonic acid groups where the calixarenes are arranged into layers, including bilayers.
AB - Lower rim O-methyl, -n-butyl, and n-octadecyl calix[4]arenes bearing p-phosphonic acid groups on the upper rim have been prepared in high yield, compounds 12−14. Where possible, the compounds have been characterized in the solid state using X-ray diffraction, or as the precursor phosphate esters or a cesium salt. The cone conformation ethyl phosphate ester for the octadecyl compound crystallizes in a bilayer 39.1 Å thick, which approaches the 40 Å of biological membranes. The 1,3-alternate cone conformation of the cesium salt of the O-methyl phosphonic acid has a metal ion coordinated to two methoxy groups, four O−P (two from neighboring calixarenes), and two η3-C3 moieties from two 1,3-disposed aromatic rings. MALDI-TOF spectra of compounds 12−14 show successive peaks corresponding to 15, 33, and 16 calixarene units, which is consistent with the intramolecular H-bonding capabilities of the diprotic phosphonic acid groups where the calixarenes are arranged into layers, including bilayers.
U2 - 10.1021/cg900315h
DO - 10.1021/cg900315h
M3 - Article
SN - 1528-7483
VL - 9
SP - 3575
EP - 3580
JO - Crystal Growth and Design
JF - Crystal Growth and Design
IS - 8
ER -