Cyanide self-addition, controlled adsorption, and other processes at layered double hydroxides.

摘要: Layered double hydroxides (LDH) are anion-exchangingmaterials of the type M(III)-M(II)x(OH)(2x+2)Y thatoccur abundantly in nature, and can concentrate, protect, andactivate simple organic anionic species possible relevance tothe earliest organisms. We now wish to report progress thefollowing areas:1) Internal vs. external uptake anions. Ferrocyanidedoes not displace carbonate from synthetic hydrotalcite (Mg:AlLDH carbonate) but is nevertheless taken up on outside theparticles. In other cases, anion controlled byspecific hydrogen bonding requirements rather than by chargedensity alone, a feature that be used control whetheruptake will both internal external, or only. These two findings together have important implications forspecific catalysis LDH, since specific willaffect individual relative conformations substrateanions, anions occupying space interlayer beunder tighter constraints those adsorbed externally.2) Specific reactions catalyzed LDH. found thatthe LDH Mg2Al(OH)6Cl catalyzes self-addition ofcyanide, give one-pot reaction at low concentrations anincreased yield diaminomaleonitrile addition, higher(≥ 0.05M) concentrations, purple-pink material adheres investigating whether this also occurswith itself, what minimum effectiveconcentration cyanide, learned about theproducts how they compare with reported high HCNconcentrations absence catalyst.