Tricyclohexyl guanidine

Another approach involved encapsulation of a bulky guanidine, N,N,N-tricyclohexyl-guanidine, in the super-cages of hydrophobic zeolite Y (Sercheli et ai, 1997). The resulting ship-in-a-bottle guanidine catalysed the aldol reaction of benzaldehyde with acetone to give 4-phenyl-4-hydroxybutan-2-one. 

The aforementioned tricyclohexyl guanidine was alternatively constructed inside the pores of a zeolite. Dicyclohexycarbodiimide was first impregnated in the porous material and reacted with cyclohexylamine. This gave a trapped base. Aseive effect keeps the molecules inside the material. 

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