Hello Together,

I made a Grignard Reaction in which I have replaced a chlorine with trimethylsilylacetylen.

This reaction worked very well, but after the purification I had to find out, that the NMR shows besides all the signals which are associated with my product/solvents, also another signal at 0.19 ppm, so most probably a second TMS group? There are no more other signals in the 1H...

In the 13C spectrum there is besides a carbon at -0.36 ppm, which is connected with the protons at 0.19 ppm, also two more tertiary carbons at 86.08 and 88.11 ppm, the region where you normally can find alkynes.

My first thought was, its trimethylsilylacetylen, but the signals of it should be in another region and it is very volatile, so it should be removed during work-up...

The non-reacted Grignard is also not possible, it was quenched after the reaction...

Does anybody maybe have a idea, what this side product could be?

Thank you very much in advance!

Best regards,

Moritz