[Hachiko]

Hi every one,
I am confused that when we compare Stille coupling and Suzuki coupling (toxicity is exception), which one is better (reactivity, regioselectivity, reaction yield,...)?
 I know that the coupling reactions are complicated with many different reactants, but when I check literature for synthesizing conjugated system, Stille coupling is more preferable. Ex: to synthesize 5,6-dinitro-4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole, they almost only use Stille coupling between 4,7-dibromo-5,6-dinitrobenzo[c][1,2,5]thiadiazole and 2-(Tributylstannyl)thiophene.
Could you please tell me which one is better and what is the reason?
Thank you!

[rolnor]

Maybe there is no real difference of importance? I think both can work fine.

[Hachiko]

Maybe there is no real difference of importance? I think both can work fine.

Because tin by-products are hardly to eliminate totally, so in electronic applications, they should use Suzuki coupling if both reaction work fine. But I see they almost use Stille reaction. It makes me confused.

[rolnor]

I have run many Stille, never any big problem with tin-byproducts?

[clarkstill]

I think "which is better" is too vague - either may be better depending on application. Which do you think is "better"?

There are certainly a lot more boronic acids commercially available than stannanes, probably because medchem prefer Suzuki (likely because of the toxicity aspects of the Stille), so you can probably generate more derivatives via Suzuki. That said, anecdotally I have always been told that if all else fails, the Stille is the most likely to work.

In a research lab, getting rid of tin waste (e.g. R3SnI) is relatively easy - I favour Harrowven's method (passing over 10%K2CO3/SiO2).

I realise this is a slightly vague collection of thoughts, but an open question gets an open answer!

[blackcat]

I have run many Stille, never any big problem with tin-byproducts?

Be aware of organotin toxicity. The removal of tin byproduct is tricky and one way is to run a K2CO3 column.

[blackcat]

Stille coupling is faster than Suzuki, and does not need water/base (for activation) and this may increase the functional tolerance of the reaction.

[Hachiko]

I think "which is better" is too vague - either may be better depending on application. Which do you think is "better"?

There are certainly a lot more boronic acids commercially available than stannanes, probably because medchem prefer Suzuki (likely because of the toxicity aspects of the Stille), so you can probably generate more derivatives via Suzuki. That said, anecdotally I have always been told that if all else fails, the Stille is the most likely to work.

In a research lab, getting rid of tin waste (e.g. R3SnI) is relatively easy - I favour Harrowven's method (passing over 10%K2CO3/SiO2).

I realise this is a slightly vague collection of thoughts, but an open question gets an open answer!

Thank you for sharing your thought. The reason make me so confused is that in the field of synthesis of conjugated monomer or polymer for electronic application(organic semiconductor, OLED, OFET, solar cell,...), almost people choose Stille coupling in stead of suzuki coupling although Suzuki coupling seems to be more safe for this application (tin waste, even ppm, can affect electronic properties of devices). It make me think that Stille coupling has some advantages.

[Hachiko]

I have run many Stille, never any big problem with tin-byproducts?

Because I read some papers that the contain of tin waste, even in ppm, can be harmful to some applications. Could you share the reason why you choose Stille coupling in your experiment?
Thank you.

[Hachiko]

Stille coupling is faster than Suzuki, and does not need water/base (for activation) and this may increase the functional tolerance of the reaction.

Yes, It may one of advantages.

[blackcat]

I think "which is better" is too vague - either may be better depending on application. Which do you think is "better"?

There are certainly a lot more boronic acids commercially available than stannanes, probably because medchem prefer Suzuki (likely because of the toxicity aspects of the Stille), so you can probably generate more derivatives via Suzuki. That said, anecdotally I have always been told that if all else fails, the Stille is the most likely to work.

In a research lab, getting rid of tin waste (e.g. R3SnI) is relatively easy - I favour Harrowven's method (passing over 10%K2CO3/SiO2).

I realise this is a slightly vague collection of thoughts, but an open question gets an open answer!

Thank you for sharing your thought. The reason make me so confused is that in the field of synthesis of conjugated monomer or polymer for electronic application(organic semiconductor, OLED, OFET, solar cell,...), almost people choose Stille coupling in stead of suzuki coupling although Suzuki coupling seems to be more safe for this application (tin waste, even ppm, can affect electronic properties of devices). It make me think that Stille coupling has some advantages.

For solar cell/OFET (e.g. polythiophene), Stille is commonly used.

However, this is not the case for OLED, where Suzuki is mainly used. Don't ask me why.

PS: I did my PhD on OLED materials.

[Hachiko]

I think "which is better" is too vague - either may be better depending on application. Which do you think is "better"?

There are certainly a lot more boronic acids commercially available than stannanes, probably because medchem prefer Suzuki (likely because of the toxicity aspects of the Stille), so you can probably generate more derivatives via Suzuki. That said, anecdotally I have always been told that if all else fails, the Stille is the most likely to work.

In a research lab, getting rid of tin waste (e.g. R3SnI) is relatively easy - I favour Harrowven's method (passing over 10%K2CO3/SiO2).

I realise this is a slightly vague collection of thoughts, but an open question gets an open answer!

Thank you for sharing your thought. The reason make me so confused is that in the field of synthesis of conjugated monomer or polymer for electronic application(organic semiconductor, OLED, OFET, solar cell,...), almost people choose Stille coupling in stead of suzuki coupling although Suzuki coupling seems to be more safe for this application (tin waste, even ppm, can affect electronic properties of devices). It make me think that Stille coupling has some advantages.

For solar cell/OFET (e.g. polythiophene), Stille is commonly used.

However, this is not the case for OLED, where Suzuki is mainly used. Don't ask me why.

PS: I did my PhD on OLED materials.

Thank you for your information. I plan to ask you why before I see that you said not to ask you:)))
I always think about the difference of choosing of coupling method.

[rolnor]

I have run many Stille, never any big problem with tin-byproducts?

Because I read some papers that the contain of tin waste, even in ppm, can be harmful to some applications. Could you share the reason why you choose Stille coupling in your experiment?
Thank you.

I had the aryltin compound so it was just simpler, if you purify by chromatography I think you can remove all traces of tin-reagent, dont worry about that.

[Hachiko]

I had the aryltin compound so it was just simpler, if you purify by chromatography I think you can remove all traces of tin-reagent, dont worry about that.
[/quote] Yes, thank you for your sharing.