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The chiral diamine (2R), (4R)-pentane-2,4-diamine (2R,4R-ptn) has been found efficiently to regulate the stereochemistry of the cobalt(III) complex [Co(edda)(2R,4R-ptn)]+(edda = ethylenediamine-N,N′-diacetate). The product ratio Λ-sym-cis:Δ-sym-cis is 3:97. The stereoselectivity is surprisingly high in comparison with that for the analogous complex involving (1R),(2R)-cyclohexane-1,2-diamine (R,R-chxn), Λ-sym-cis:Δ-sym-cis= 60:40. It is discussed on the basis of crystal structure determinations carried out for both diastereoisomers of sym-cis-[Co(edda)(2R,4R-ptn)]+. A notable difference was observed in the six-membered chelate ring of 2R,4R-ptn which adopts the chair conformation in Λ-sym-cis-[Co(edda)(2R,4R-ptn)]ClO4·H2O 1a but the λ skew-boat conformation in Δ-sym-cis-[Co(edda)(2R,4R-ptn)]ClO41b. The chair conformation in 1a is due to steric repulsions between the chelates, which is the important factor for the preferential formation of 1b over 1a. Such steric repulsions between the chelates are remarkably efficient for the chiral six-membered chelate compared with those for the five-membered one. N-Alkyl substitutions on the edda ligand caused preferential formation of the Λ-sym-cis form, as is the case for the [Co(R2edda)(R,R-chxn)]+ system.

The incomplete cubane-type cluster, [Mo3S4(H2O)9]4+, and the complete cubane-type cluster, [Mo3NiS4(H2O)9Cl]3+, are incorporated into 12-membered ring zeolites by ion exchange, leading to catalysts which are highly selective for C2 formation from CO–H2.

A series of octahedral cobalt(III) complexes involving a tetradentate diaminedicarboxylate and a chiral diamine was prepared: [CoL(am)]+ where L = ethylenediamine-N,N′-diacetate (edda2–), or its N,N′-dimethyl (dmedda2–) and N,N′-diethyl (deedda2–) derivatives; am =(1R),(2R)-cyclohexane-1,2-diamine (R,R-chxn), or its N,N′-dimethyl (R,R′-dmchxn) and N,N′-diethyl (R,R-dechxn) derivatives. The complexes were separated into their diastereoisomers using cation-exchange column chromatographies, and characterized by elemental analyses, electronic absorption, circular dichroism and 13C NMR spectroscopies The crystal structure of a dominant product in the [Co(edda)(R,R-dmchxn)]+ system, (–)550[Co(edda)(R,R-dmchxn)]ClO4·H2O, has been established, and the stereochemistry determined to be Δ-sym-cis; orthorhombic, space group P212121, a= 13.469(2), b= 19.184(3), c= 7.917(1)A, Z= 4, R= 0.067, R′= 0.055, N-Alkyl substitutions on the edda ligand and those on the R,R-chxn ligand influence the stereochemistry of the cobalt(III) complexes in different ways. The former caused stereoselective formation of ∧-sym-cis forms, the latter preferential formation of Δ-sym-cis forms. High stereoselectivity was observed in the formation of [Co(deedda)(R,R-chxn)]+, yielding a final product distribution of 96%∧-sym-cis and 4%Δ-sym-cis forms, whereas [Co(edda)(R,R-dechxn)]+ yielded 2%∧-sym-cis and 98%Δ-sym-cis forms. The latter is due to steric interaction between N-alkyl substituents in the R,R-chxn chelate and acetate rings in the edda chelate, while the former is due to steric interaction between N-alkyl substituents in the edda chelate and NH in the R,R-chxn chelate. Such interactions are efficient in steric regulation of octahedral cobalt(III) complexes.

Sodium 1-amino-4-bromoanthraquinone-2-sulphonate is photo-aminated to form sodium 1-amino-4-alkylaminoanthraquinone-2-sulphonate with ammonia or alkylamines in aerated aqueous alcohol.