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Why does reduction not go to completion with LiAlH4
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Adam Brower
Why does reduction not go to completion with LiAlH4
CHI? you mean CH2?
It doesnt mean anything, some aminoalcohol still can be formed and reduce the reactivity of LAH. DO you know what are the other products (the rest 40%)?
It doesnt mean anything, some aminoalcohol still can be formed and reduce the reactivity of LAH. DO you know what are the other products (the rest 40%)?
Your product will be an amino alcohol. This may well react with LiAlH4 and reduce it's reducing ability. Much like treating LiAlH4 with tert-butanol to modify its reactivity. Try the reaction at reflux. Try adding more LiAlH4. Try a different reducing agent.
Your product will be an amino alcohol. This may well react with LiAlH4 and reduce it's reducing ability. Much like treating LiAlH4 with tert-butanol to modify its reactivity. Try the reaction at reflux. Try adding more LiAlH4. Try a different reducing agent.
Hey Acadasol, sorry to hear about your unsatisfactory yields... even the most reliable reactions can sometimes give us crappy results... For context can you perhaps show us what you're trying to reduce so that the issue can be troubleshooted and solutions given from an informed perspective?
Hey Acadasol, sorry to hear about your unsatisfactory yields... even the most reliable reactions can sometimes give us crappy results... For context can you perhaps show us what you're trying to reduce so that the issue can be troubleshooted and solutions given from an informed perspective?
Since LiAlH4 is a reducing agent for amides, it should successfully reduce your Lactam group in theory. Given your 58% yield, it sounds to me like some type of reaction occurred, but side reactions also occurred. Perhaps a procedural step was the issue, as you did not clarify the process that you used to perform your reduction. For instance, did you correctly perform an acid work up with your solution, presumably dissolved in diethyl ether?
In the reference paper, confidentially, the yield was also 58%. So, I was thinking perhaps LiAlH4 couldn't reduce all of the starting material. I worked the reaction up by gradually dropping crystals of NaSO4 into the reaction mixture to evolve hydrogen gas. And the organic layer was separated with diethyl ether. My product is a cyclic amine. Is it possible that some of the spots that I get reduce the reducing ability of LiAlH4
Since LiAlH4 is a reducing agent for amides, it should successfully reduce your Lactam group in theory. Given your 58% yield, it sounds to me like some type of reaction occurred, but side reactions also occurred. Perhaps a procedural step was the issue, as you did not clarify the process that you used to perform your reduction. For instance, did you correctly perform an acid work up with your solution, presumably dissolved in diethyl ether?
In the reference paper, confidentially, the yield was also 58%. So, I was thinking perhaps LiAlH4 couldn't reduce all of the starting material. I worked the reaction up by gradually dropping crystals of NaSO4 into the reaction mixture to evolve hydrogen gas. And the organic layer was separated with diethyl ether. My product is a cyclic amine. Is it possible that some of the spots that I get reduce the reducing ability of LiAlH4
Since LiAlH4 is a reducing agent for amides, it should successfully reduce your Lactam group in theory. Given your 58% yield, it sounds to me like some type of reaction occurred, but side reactions also occurred. Perhaps a procedural step was the issue, as you did not clarify the process that you used to perform your reduction. For instance, did you correctly perform an acid work up with your solution, presumably dissolved in diethyl ether?
Since LiAlH4 is a reducing agent for amides, it should successfully reduce your Lactam group in theory. Given your 58% yield, it sounds to me like some type of reaction occurred, but side reactions also occurred. Perhaps a procedural step was the issue, as you did not clarify the process that you used to perform your reduction. For instance, did you correctly perform an acid work up with your solution, presumably dissolved in diethyl ether?
In my opinion, the mechanism suggests a difficulty in this reaction. The problem as I see it is that it is difficult to eliminate the oxygen. It must come out as an aluminum oxide. As I recall, typically procedures use an incremental addition of LAH and the yields are never as high as ketone or ester reductions.
In my opinion, the mechanism suggests a difficulty in this reaction. The problem as I see it is that it is difficult to eliminate the oxygen. It must come out as an aluminum oxide. As I recall, typically procedures use an incremental addition of LAH and the yields are never as high as ketone or ester reductions.
I tried to reduce macrocyclic amide to amine by LiAlH4 and it didnt work at all. After literature search, I found out that others had same problem reducing very similar compound using LiAlH4, BH3 etc.. about 5 reducing agent tried and none of those worked.
I tried to reduce macrocyclic amide to amine by LiAlH4 and it didnt work at all. After literature search, I found out that others had same problem reducing very similar compound using LiAlH4, BH3 etc.. about 5 reducing agent tried and none of those worked.
Your product will be an amino alcohol. This may well react with LiAlH4 and reduce it's reducing ability. Much like treating LiAlH4 with tert-butanol to modify its reactivity. Try the reaction at reflux. Try adding more LiAlH4. Try a different reducing agent.
My product is actually an amine. The CO was reduced to CHI with 2 equivalent LiAlH4
Your product will be an amino alcohol. This may well react with LiAlH4 and reduce it's reducing ability. Much like treating LiAlH4 with tert-butanol to modify its reactivity. Try the reaction at reflux. Try adding more LiAlH4. Try a different reducing agent.
My product is actually an amine. The CO was reduced to CHI with 2 equivalent LiAlH4
It doesnt mean anything, some aminoalcohol still can be formed and reduce the reactivity of LAH. DO you know what are the other products (the rest 40%)?
Yes, I meant methylene. That was a typo. Meanwhile, I didn't collect the other product. But, there were other spots.
It doesnt mean anything, some aminoalcohol still can be formed and reduce the reactivity of LAH. DO you know what are the other products (the rest 40%)?
Yes, I meant methylene. That was a typo. Meanwhile, I didn't collect the other product. But, there were other spots.
With 40% of other products it would be worth isolating them and finding out what they are. It may help you understand what is going on in this reaction.
With 40% of other products it would be worth isolating them and finding out what they are. It may help you understand what is going on in this reaction.
It doesnt mean anything, some aminoalcohol still can be formed and reduce the reactivity of LAH. DO you know what are the other products (the rest 40%)?
It doesnt mean anything, some aminoalcohol still can be formed and reduce the reactivity of LAH. DO you know what are the other products (the rest 40%)?
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Try the reaction at reflux.
Try adding more LiAlH4.
Try a different reducing agent.
Try the reaction at reflux.
Try adding more LiAlH4.
Try a different reducing agent.
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In the reference paper, confidentially, the yield was also 58%. So, I was thinking perhaps LiAlH4 couldn't reduce all of the starting material. I worked the reaction up by gradually dropping crystals of NaSO4 into the reaction mixture to evolve hydrogen gas. And the organic layer was separated with diethyl ether. My product is a cyclic amine. Is it possible that some of the spots that I get reduce the reducing ability of LiAlH4
In the reference paper, confidentially, the yield was also 58%. So, I was thinking perhaps LiAlH4 couldn't reduce all of the starting material. I worked the reaction up by gradually dropping crystals of NaSO4 into the reaction mixture to evolve hydrogen gas. And the organic layer was separated with diethyl ether. My product is a cyclic amine. Is it possible that some of the spots that I get reduce the reducing ability of LiAlH4
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My product is actually an amine. The CO was reduced to CHI with 2 equivalent LiAlH4
My product is actually an amine. The CO was reduced to CHI with 2 equivalent LiAlH4
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Yes, I meant methylene. That was a typo. Meanwhile, I didn't collect the other product. But, there were other spots.
Yes, I meant methylene. That was a typo. Meanwhile, I didn't collect the other product. But, there were other spots.
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