
TY  - JOUR
A1  - Asfari, Z 
A1  - Harrowfield, JM 
A1  - Sobolev, AN 
A1  - Vicens, J 
T1  - Structural Characterization of a Calix[4]arene Constrained to a 1,3-Alternate Conformation by Polyether Bridging
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1994
VL  - 47
IS  - 4
SP  - 757
EP  - 762
KW  - 
UR  - https://doi.org/10.1071/CH9940757 
N2  - Despite evidence of coordinative interactions with alkali metal picrates in solution, attempts to crystallize Li+, Na+, K+, Rb+ or Cs+ complexes of a 'doubly crowned' calix [4] arene (obtained by reaction of tetraethylene glycol ditosylate with p-t- butylcalix [4] arene ) have resulted only in the deposition of crystals of the free ligand . A room-temperature single-crystal X-ray study has shown the crystals to be hexagonal, space group P6422, a (= b) 17.092(5), c 20.147(7) &#506;, V 5097(5) &#506;3, Z 3, conventional R (on |F|) 0.082 for 1397 'observed' reflections [I > 3&#963;(I)]. The highly symmetrical oblate-globular shape of this doublecrowncalix allows the enclosure of an extended narrow cavity possibly better suited to the binding of two small metal ions rather than one large. 
ER  -

