[huutrong]

I did the first reaction and I receive two products. The second one is main product.
But, when I did the second reaction I can not find my expected product. And do not understand why ?
I think it will happen. I let the reaction in 22h, but the starting material is still not consumed.
Is there anyone can give me an explanation for the second reaction.

Thank you very much.

[discodermolide]

If you can can you provide some reaction conditions?

[huutrong]

Ah, the reaction was in THF solvent, in -78oC and I used Lithium Diisopropylamine as base. After finishing add the reagents into the reaction mixture at -78oC the reaction was brought to room temperature.
I just wonder why at the first time the reaction can happen in two ways with two products, but when I made it again it can not happen !! In fact I can see the products, but it's just a little compare to the starting material. I will try to isolate it again and consider what it is. But It also does not satisfy my expectation.
I think that it's easier with propargyl bromide. ^^, But the truth is totally different.

[discodermolide]

In the case of propargyl bromide surely the acetylenic proton is the most acidic, so you may be getting polymerisation.