If, say, propenal undergoes nucleophilic addition of hydrazine, will the 1,2- adduct or the 1,4-adduct be preferred? Why?

There is an obvious reasonace structure with an electrophilic beta carbon so under proper conditions will the 1,4-adduct dominate?

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    $\begingroup$ Organocuprates have much higher tendency to add in a 1,4- fashion. Selectivity can be tuned as a function of the reagent (usually). $\endgroup$ – Zhe Aug 15 '19 at 15:49
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    $\begingroup$ Google for 'Michael addition' and you'll find that in fact plenty of nucleophiles add 1,4-. $\endgroup$ – orthocresol Aug 15 '19 at 16:39
  • $\begingroup$ @orthocresol I found out about the Michael addition after posting this question but I can't find anything about hydrazine adding 1,4 to an enone. My textbook mentions a similar addition reaction producing a 1,2-adduct. So I'm confused when I should rule out the 1,4- adduct. $\endgroup$ – Fᴀʀʜᴀɴ Aɴᴀᴍ Aug 15 '19 at 16:42
  • $\begingroup$ That's because hydrazine is special: it has two NH2 groups, so one can condense with the carbonyl group to form an imine, and the other one can add to the double bond. $\endgroup$ – orthocresol Aug 15 '19 at 16:44
  • $\begingroup$ @orthocresol So does that mean the product wouldn't be a hydrazone as one might expect? $\endgroup$ – Fᴀʀʜᴀɴ Aɴᴀᴍ Aug 15 '19 at 16:46

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