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I have read there exist so called "magic" (super strong) acids which can provide a proton to saturated hydrocarbons, producing cation and hydrogen molecule. Can hydrides act in the same manner (pick a proton to form free hydrogen molecule)? And why?

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  • $\begingroup$ Depends on hydride. $\endgroup$
    – Mithoron
    Dec 7, 2018 at 20:19

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The pKa of sodium or lithium hydride is (solvent dependent) about 35, the pKa of Butyl lithium is around 50 so clearly H- is not strong enough to tear a proton off an unactivated alkane pKa tables here

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    $\begingroup$ Then again, cyclopentadiene is also a hydrocarbon, so... $\endgroup$
    – Ivan Neretin
    Dec 7, 2018 at 19:43
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    $\begingroup$ Not exactly unactivated though as the cyclopentadienyl anion is aromatic $\endgroup$
    – Waylander
    Dec 7, 2018 at 19:56
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    $\begingroup$ True, but there was no "unactivated" in the original question. $\endgroup$
    – Ivan Neretin
    Dec 7, 2018 at 20:03
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    $\begingroup$ The OP asked about saturated hydrocarbons, which excludes cyclopentadiene, $\endgroup$
    – Waylander
    Dec 7, 2018 at 20:45
  • $\begingroup$ OK, I stand corrected. $\endgroup$
    – Ivan Neretin
    Dec 7, 2018 at 23:35

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