New routes to the preparation of two families of small pore microporous solids are described. Flexible diquaternary alkyl ammonium cations (C4H8)CH3N+(CH2)nN+CH3(C2H8), n = 3–5, have been found to act as structure directing agents in the synthesis of aluminophosphate-based materials of the ABC-6 group. The templates exhibit considerable selectivity in crystallising phases of the ERI or AFX-type (MeAPO-17 or MeAPO-56, respectively) from a wide variety of metalloaluminophosphate gels (Me = Mg2+, Co2+ or Si4+). For example, from gels containing Mg/P = 0–0.25, 1,4-bis(N-methylpyrrolidinium)butane cations gave MgAPO-17, and 1,5-bis(N-methylpyrrolidinium)pentane cations gave MgAPO-56. Notably, materials could be prepared with levels of metal-substitution tailored to a high degree and distributed non-randomly within the framework. As-prepared solids have been characterised by powder XRD, multinuclear solid state NMR, FT-IR, SEM, and thermal and elemental analysis.
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