Control of open-framework structures through template⋯template interactions? Syntheses and structures of C2H7N4O⋅ZnCl(HPO4) and (C2H7N4O)2⋅Zn3(H2O)(HPO3)4

The syntheses and structures of C2H7N4O⋅ZnCl(HPO4) and (C2H7N4O)2⋅Zn3(H2O)(HPO3)4 are reported. Both phases arose in solution mediated reactions by way of the controlled, in situ, preparation of the cationic [C2H7N4O]+ guanylurea template by the slow hydrolysis of the neutral 2-cyanoguanidine starting material. C2H7N4O⋅ZnCl(HPO4) contains anionic [ZnCl(HPO4)]− 63-topology polyhedral layers built up from vertex-sharing ZnO3Cl and HPO4 polyhedra. (C2H7N4O)2⋅Zn3(H2O)(HPO3)4 is also layered and contains ZnO4, ZnO3(H2O) and HPO3 polyhedra sharing vertices by way of ZnOP bonds. In both structures, the guanylurea template participates in numerous template-to-framework and also template-to-template hydrogen bonds. Strikingly, the arrangement of template-to-template H bonds is different in the two structures, and also different to that seen earlier in C2H7N4O⋅ZnPO4. Crystal data: C2H7N4O⋅ZnCl(HPO4), Mr=299.91Mr=299.91, monoclinic, Cc   (No. 9), a=4.8823(2) Åa=4.8823(2) Å, b=25.4781(11) Åb=25.4781(11) Å, c=8.0335(4) Åc=8.0335(4) Å, β=105.496(1)°β=105.496(1)°, V=962.98(7) Å3V=962.98(7) Å3; Z=4Z=4. (C2H7N4O)2⋅Zn3(H2O)(HPO3)4, Mr=740.27Mr=740.27, triclinic, P1¯ (No. 2), a=9.0022(5) Åa=9.0022(5) Å, b=9.5211(5) Åb=9.5211(5) Å, c=13.4933(7) Åc=13.4933(7) Å, α=94.986(1)°α=94.986(1)°, β=94.111(1)°β=94.111(1)°, γ=99.051(1)°γ=99.051(1)°, V=1133.51(1) Å3V=1133.51(1) Å3; Z=2Z=2.

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