If you want to make the reaction of propargyl amine with aldehyde selectively not problems, the reaction can happen just in ethanol.

Amine + Aldehyde: Yes stirring in ethanol is OK, you should also be able to extract the reaction water by means of the Dean Stark method.

However if you are thinking about the reaction of propyne (methylacetylene) with your aldehyde compound selectivity may become more difficult.

Please specify which reaction do you mean?

I want to propargylate 3-bromo pyridine-4-aldehyde

Hi,

Again, same question: what structure, exactly, do you want to make?

Bill

The compound name which I want to synthesize is

1-(3-bromopyridin-4-yl)-3-phenylprop-2-yn-1-ol

The name is generated by chemdraw. So kindly paste it in chemdraw and you will get the structure.

Thank you

Sandeep

Hi,

See the attached. SciFinder says that a variety of RM, where M = MgBr, Zn, and Li; R = Aryl, allyl, or alkyl, mainly add to the aldehyde and do not displace the Br. I suggest you try Phenylethynyl lithium first.

Bill

Hi,

See the attached.

Bill

Thank you William,!!

Could you tell me what was your search option in scifi?

I was going to try the lithium, but was sceptic that it would add on to the pyridine ring as well.

With Mg, I was worried it would add across C-Br bond.

Hi,

I started with the bromo-aldehyde and drew the alcohol product of the addition of one carbon; i.e. 1-(3-bromopyridin-4-yl)ethanol. I then filtered out any reactants which were not R-Metals, and was left with those transmitted.

By the way, if you see him, please give my regards to Prof Robert Carlson. We were schoolmates many years ago.

Happy Holidays!

Bill

Thank you for your suggestions.

I see Dr Carlson everyday, will definitely convey your regards to him.

Happy holidays to you too!

Sandeep

Its dead easy under Barbier conditions, see Tet Lett., 1996, 37, 8049-8052. Just mix propargyl bromide, zinc powder and aldehyde in THF at rt and stir overnight. No special precautions needed.

Jones,

Looks neat ! Any specific sequence of addtion. May be add Zn and propargyl bromide stir for a while then add aldehyde?

What do you suggest?!!

Thanks you

Sandeep

Keith,

There is slight problem here. There is an exctra methylene group in the chain.

What I wish is to form a bond between sp carbon of alkyne source and the carbonyl carbon !!!

Thanks

Sandeep

OK. I should read more carefully!

Nevermind, I learnt a new reaction from you !