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A reaction of organocadmium

In the above reaction, I was told that the reason organocadmium reacts only with aryl chloride segment is because it is very less reactive and reacts only with most reactive sites. This was consistent with my previous beliefs that we always react most electrophilic and most nucleophilic reagents.

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In this reaction also there are two electrophilic sites and I was expecting a major product from carbonyl site but opposite was true. The explanation was given that soft nucleophile prefers soft electrophiles while hard nucleophiles prefer hard electrophiles. The explanation seemed credible to me but contradictory to previous one.

Where am I going wrong?

I don't know if I have made my doubt clear enough. I am new to the community and any suggestions on improving the questions are welcome.

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  • $\begingroup$ HSAB theory is pretty dodgy. The "true" explanations for some of these things are usually rather more complicated, so people came up with this notion of "hard" and "soft" to explain some phenomena. The problem is that it's quite tautological: the HSAB concept only seems to make sense when applied precisely to these phenomena. Take it with a huge pinch of salt whenever you see it, and don't try to stretch it beyond the contexts that it's applied to. See e.g. onlinelibrary.wiley.com/doi/full/10.1002/anie.201007100 for a refutation of HSAB arguments. $\endgroup$
    – orthocresol
    Commented Apr 30, 2021 at 22:28
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    $\begingroup$ For what it's worth, there's a good underlying question in here, i.e. why does HSAB theory fail in some cases. It's a shame that the example used, i.e. Me2Cd plus this 1,4-aromatic, is made up. If someone can find a real example, that would make this much better. (I strongly suspect that organocadmiums have been out of favour for... a while now.) $\endgroup$
    – orthocresol
    Commented Apr 30, 2021 at 22:42

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