Question

The conjugate hase of 19.28 forms the complex ol which has mer- and fae-isomers. (a) Draw the structures of these isomers, and explain why the labels mer and fac are used. (b) What other type of merism does IColil ethibit? (c) When a freshly prpured sample of [Col] is chromatographed, two fractions. A and B. are collected. The F NMR sirum of A exhibits a singlet. while that of B shows three signals with relative integrals of 1:1:1. Rationalize these data. CF HC HL (19.28) &

Answer 1

Compound 19.28 will loose it's most acidic proton and will form an anionic conjugate base which can bind with the Co3+ metal centre and forms 2 different isomers ( fac and mer). Using chromatography they can be separated as they have 2 different structures.

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