junkchemie
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preparation of LiBH4 and LiAlH4 solution in THF
I checked in the internet that LiBH4 is quite soluble in THF about 25g in 100ml that gives around 11.5(M) strength approx. Also there are commercial
solution available labelled as 2.0(M), etc.
When I tried to dissolve LiBH4(55mg) powder in dry THF(25ml) that should give 0.1(M) strength; surprisingly, its forming dispersion even on several
hours of stirring with a magnetic pellet under Nitrogen.The white powder settles down on stopping the agitation. I expected clear solution like the
commercial ones....any inputs will be helpful
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bnull
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Mood: "Ah, what the hell; it's Christmas!" - Carmine Lorenzo
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Are you sure it's LiBH4? Is it new?
Quod scripsi, scripsi.
B. N. Ull
P.S.: Did you know that we have a Library?
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junkchemie
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I collected from an organic lab just below my lab; they said it's working well for them!
the bottle is not new and from Aldrich
Similar thing happening with LiAlH4, with similar molarity of 0.1
Today I sonicated a little stirred suspension but no result
I am planning to synthsize using NaBH4 and LiBr in THF....if it works its ok...but this is not the solution
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Lionel Spanner
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The figure for solubility in diethyl ether I've seen quoted is 2.5 g per 100 mL (10 times less); in my experience, these figures tend to be very
optimistic.
For what it's worth, I also know from experience that sodium borohydride is nearly insoluble in THF, so I wouldn't expect the lithium salt to be much
more soluble.
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