FormerBeagle
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Aluminum hydride from LiAlH4
I have seen reference to adding small amounts of 100% sulfuric acid to LiAlH4 to make a more active reducing agent. My understanding is that this
produces aluminum hydride. In my own work, I have used the addition of AlCl3 to LAH for more stubborn functional groups. Is there some advantage to
the sulfuric acid method?
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draculic acid69
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What does adding alcl3 to LAH do?
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FormerBeagle
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It increases the reducing activity quite a bit by converting it to aluminum hydride. For instance, for N-monoalkyl tryptamines, LAH by itself only
sluggishly reduced the amides. The addition of AlCl3 dramatically decreased reaction times.
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Keras
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You can also boost the reducing power of sodium borohydride using various mineral additives. IMO, sodium borohydride is much cheaper and easier to
store and handle than lithium-aluminium hydride.
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