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I have a 25-gram bottle of solid LDA (lithium diisopropylamide), factory sealed. I'm going to setup an aldol reaction with it, but I don't know how to organize work properly.

I think of quickly weighing some amount into a flask flushed with argon and flushing the bottle with argon for storage. Then I'll dissolve the LDA in the flask in THF and use this solution. The only concern is stability of the rest of LDA in bottle.

If you have some ideas how to organize it better, please share.

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  • $\begingroup$ The best way is to order solution of LDA in THF, which is available commercially in 1 M or 3 M concentrations. If you already have the solid, you may use it as suggested. We have used LAH in solid form (which is highly flammable) without trouble in that way (even using $\ce{N2}$ to flush it). $\endgroup$ Apr 9 at 15:37
  • $\begingroup$ @MathewMahindaratne the solution is obviously better, but if I order it now it will arrive in couple months (we have delivery troubles) $\endgroup$ Apr 9 at 15:44
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    $\begingroup$ Once you open it, it’s not going to last long without a glovebox. You’d be best quickly making up a few flasks of a solution and sealing them under N2. Much easier to dispense $\endgroup$
    – NotEvans.
    Apr 9 at 16:17
  • $\begingroup$ I agree with @NotEvans. Dissolve the whole lot in THF under nitrogen and store it in the fridge. Titrate a sample every time you plan to use it $\endgroup$
    – Waylander
    Apr 9 at 16:46

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