Chiral Germanium Zeotype with Interconnected 8-, 11-, and 11-Ring Channels. Catalytic Properties

The synthesis, structure, thermal stability, and catalytic properties are reported for a chiral germanate, Ge9O19(OH)2(N2C2H10)2(N2C2H8)0.5H2O, ICMM6. It is orthorhombic, of space group C2221, and has unit cell dimensions a = 12.156(3) A, b = 13.960(4) A, c = 14.258(4) A, volume 2419.6(11) A3, and Z = 4. Three kinds of interconnected helical 8-, 11-, and 11-rings channels are present in the 3D framework. ICMM6 is an active chiral catalyst for the Michael addition reaction and acetalization of aldehydes. It is stable in water and organic solvents and can be recovered and reused at least four times without losing either its structure or its reactivity.