Decent references for SN2 displacement of tosylate with acetylide

AI Thread Summary
The discussion centers on challenges faced while lithiating a terminal alkyne and subsequently reacting the resulting acetylide with a tosylate. The initial procedure involved using THF at -78°C, adding nBuLi and tosylated phenylethanol, followed by an ammonium chloride workup. Despite observing a color change, the resulting NMR and TLC analyses indicated a mixture of starting materials, leading to confusion about the failure of the reaction. Suggestions for improvement included the potential addition of ethylenediamine or TMEDA to enhance the reaction. Ultimately, the user found success by incorporating 20% v/v DMSO and warming the mixture after adding the tosylate, indicating that solvent choice and reaction conditions significantly impact the outcome.
burningbend
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i'm having trouble finding good references for lithiating a terminal alkyne and reacting that acetylide with a tosylate, and my goto procedure didn't work. can anyone give me a hand?

procedure i did try:

alkyne in THF at -78
1.0 eq nBuLi added
1.0 eq tosylated phenylethanol added (color change here) still at -78
ammonium chloride workup

despite the color change, the NMR and TLC just show a mixture of starting materials and I'm a bit baffled as to why our normal run-through didn't succeed. maybe adding ethylenediamine or TMEDA is necessary?
 
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meh, pretty sure i fixed it by adding 20% v/v DMSO and warming after adding the tosylate.
 

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