Hello dear friends!

I have a question about a reaction route in my thesis. I am synthesized thiosemicarbazide then in alkaline/acidic medium is synthesized from thiosemicarbazide to triazoles/thiadiazoles.However alkyl isotiyosyanate as methyl/ethyl/cyclohexyl can be thiosemicarbazide,  2-pieridino ethyl and 2-(4-morpholino) ethyl isothiosyanate isn't thiosemicarbazide and is directly transforming triazole. But I don't want to direct this cyclization. Because thiazdiazoles obtain from that thiosemicarbazides.I want to get morpholino and piperidino ethyl thiadiazole. May are you doing advice this difficult problem. 

thanks everyone !

Edited January 25, 20187 yr by ismailcelik

Not strictly related, but I believe you are missing a carbon in your unexpected product. 

As for your issue, you could try acidifying the hydrazide slightly. I have also had success with these reactions through refluxing in toluene. Admittedly, I was using aromatic isothiocyanates, but it’s a simple enough modification to try.

10 hours ago, ismailcelik said:

Hello dear friends!

I have a question about a reaction route in my thesis. I am synthesized thiosemicarbazide then in alkaline/acidic medium is synthesized from thiosemicarbazide to triazoles/thiadiazoles.However alkyl isotiyosyanate as methyl/ethyl/cyclohexyl can be thiosemicarbazide,  2-pieridino ethyl and 2-(4-morpholino) ethyl isothiosyanate isn't thiosemicarbazide and is directly transforming triazole. But I don't want to direct this cyclization. Because thiazdiazoles obtain from that thiosemicarbazides.I want to get morpholino and piperidino ethyl thiadiazole. May are you doing advice this difficult problem.

thanks everyone !

 

 

My previous suggestions still apply. Let me know how you go. 

Ok. hypervalent_iodine, a a lot of thanks.