Destroyer # 131 orgo

[monsieurwise]

For the first reaction, why the grignard works like that? I mean I know the grignard is a nucleophile, but then isn't a lone pair next to a triple bond on a carbon super hard to make?
Thanks guys!!!

 

[athomas]

You're making an acetylide ion, just like you would if you were using NaNH2 in NH3. The Grignard is a VERY strong base, so yes, it will deprotonate a terminal alkyne even though that H isn't normally acidic.

 

[monsieurwise]

Thank you so much! So only NaNH2 and Grignard can do that right? Thanks =)

 

[athomas]

I think any really strong base like NaN2 in liquid ammonia, a grignard, butyllithium, and maybe LDA. Our typical strong base NaOH isn't strong enough.

https://en.wikipedia.org/wiki/Acetylide
http://www.bluffton.edu/~bergerd/classes/cem221/Handouts/syntheticUtilityAlkynes_a.pdf

 

[monsieurwise]

Thank you!