Cation-controlled capture of polyoxovanadate-based organic–inorganic 1D architectures

Abstract

Metal cations are used to control the selective crystallization of organic-inorganic supramolecular polymers. Two complementary monomers, a dodecanuclear vanadate [V12O32(NO3)]5- and the organic macrocycle cyclen assemble into hybrid host-guest aggregates....

Mechanistic insights into template-driven polyoxovanadate self-assembly: the role of internal and external templates

“…Halide template insertion into the {V 12 } structure was explored by modification of the original {V 12 } -cyclen synthesis reported earlier. 19 Briefly, the new synthesis uses reaction of ( n Bu 4 N) 4 [V 4 O 12 ] (= {V 4 } ), cyclen and a metal salt to introduce the template anion (La(NO 3 ) 3 , LaCl 3 , LaBr 3 , BaBr 2 ) in DMSO solution acidified with the corresponding (template-containing) acid ( i.e. HNO 3 /HCl aq /HBr aq ).…”

“…Note that an earlier study had shown that the use of a La 3+ or Ba 2+ as counter-cation allows selective isolation of the {V 12 } capped with diprotonated cyclen (Table 1, compound 5 ) or triprotonated cyclen (Ba 2+ , Table 1, compound 4 ). 19…”

“…Halide template insertion into the {V 12 } structure was explored by modification of the original {V 12 }-cyclen synthesis reported earlier. 19 Briefly, the new synthesis uses reaction of (nBu 4 N) 4 Note that an earlier study had shown that the use of a La 3+ or Ba 2+ as counter-cation allows selective isolation of the {V 12 } capped with diprotonated cyclen (Table 1, compound 5) or triprotonated cyclen (Ba 2+ , Table 1, compound 4). 19 Next, we used crystallographic structural analysis to examine how changes of the internal template affect the cyclen-{V 12 } interactions in the crystal lattice, see Fig.…”

“…1a). 19 This initial study showed that the di-or triprotonated cyclen interacts with the {V 12 } framework and binds selectively at the "open" face of the cluster, close to the internal template (Fig. 1a), resulting in the formation of infinite 1D chains in the crystal lattice (Fig.…”