Metal-organic structural body

A metal-organic framework comprising a multivalent metal ion and a carboxylate ion of formula [I]:

• wherein in formula [I],
• X1 to X3 each independently represent a functional group of formula [II]:
• *—ZCO2−)k [II]
• wherein in formula [II], Z is a single bond or a multivalent linking group, k is an integer of 1 to 4, and * is the position at which a bond is formed with a benzene ring and has also the same meaning in the following;
• R1 to R3 each independently represent a hydrogen atom, a C1-6 alkyl group, a C3-8 cycloalkyl group, a C6-10 aryl group, a 3 to 6-membered heterocyclyl group, a C1-6 alkoxy group, a C6-10 aryloxy group, a heteroaryloxy group, a halogeno group, C1-6 haloalkyl group, a C6-10 haloaryl group, a C1-6 haloalkoxy group, C1-6 alkylthio group, a C6-10 arylthio group, a heteroarylthio group, a C1-6 alkylsulfinyl group, a C6-10 arylsulfinyl group, a heteroarylsulfinyl group, a C1-6 alkylsulfonyl group, a C6-10 arylsulfonyl group, a heteroarylsulfonyl group, a cyano group, a nitro group or a group of formula [III]:
• wherein in formula [III], R11 and R12 each independently represent a hydrogen atom, a C1-6 alkyl group, a C6-10 aryl group, a C1-6 alkylcarbonyl group or a C6-10 arylcarbonyl group;
• a is the number of X1 and is 0, 1, 2, 3 or 4, and when a is 2 or more, a plurality of X1s is the same as or different from each other;
• a1 is the number of R1 and is 0, 1, 2, 3 or 4, and when a1 is 2 or more, a plurality of R1s is the same as or different from each other;
• b is the number of X2 and is 0, 1, 2, 3 or 4, and when b is 2 or more, a plurality of X2s is the same as or different from each other;
• b1 is the number of R2 and is 0, 1, 2, 3 or 4, and when b1 is 2 or more, a plurality of R2s is the same as or different from each other;
• c is the number of X3 and is 0, 1, 2, 3 or 4, and when c is 2 or more, a plurality of X3s is the same as or different from each other;
• and
• c1 is the number of R3 and is 0, 1, 2, 3 or 4, and when c1 is 2 or more, a plurality of R3s is the same as or different from each other;
• provided that a+b+c is 2 or more;
• and
• Y1 and Y2 each independently represent a hydrogen atom, a halogeno group, a C1-6 alkyl group or a C1-6 alkoxy group, provided that when the multivalent metal ion is a trivalent metal ion, Y1 and Y2 each independently represent a halogeno group, a C1-6 alkyl group or a C1-6 alkoxy group;
• wherein the carboxylate ion and the multivalent metal ion are bound to each other.