Column chromatography amine metal complexes

Careful studies of this reaction indicate, that besides 1 1 cyclization products, 2 2 compounds and linear tosylated amines are often produced <87HCA680>. Sometimes purification can be achieved by fractional crystallization, but in several cases column chromatography was needed. Separation of the 1 1 and 2 2 cyclization products from each other can also be done by complexation with an appropriate metal ion. For example, the binuclear Cu + complex of [24]Ng was isolated and purified from the 1 1 cyclization product [12]Nj <88IC1641>. 

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