dermolotov
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Buchwald Hartwig Cross Coupling - Any Stories?
Tossing out a wild question here in hopes of answers.
After two failed attempts with a Pd-catalysed Cross Coupling, do any of you people have any ideas on this specific reaction?
Degassed 3 times over liquid nitrogen and will try further on to use dry ice in acetone.
Does anyone have any stories of Pd-Catalysis and advice moving forward? Any advice regarding temperature, pressure, etc? All the time, it seems that
the OTf is eaten up and what remains does not show up on the phosphorous NMR.
I might work this reaction up in a glovebox over a smoldering powder of copper.
Will hope to get something better moving forward in the next month or so. I am reluctant to attempt the reaction a third time by Einstein's definition
of insanity. Also because I will have to move the reaction to somewhere a schlenk line is not accessible.
On that line, I'd appreciate any stories of succeeded or tried and failed BookForest HardWig reactions.
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AvBaeyer
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A good deal of the Buchwald-Hartwig chemistry is frankly unreproducible. I have heard about and seen too many failures with this chemisrty. Good luck.
AvB
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dermolotov
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Quote: Originally posted by AvBaeyer  | A good deal of the Buchwald-Hartwig chemistry is frankly unreproducible. I have heard about and seen too many failures with this chemisrty. Good luck.
AvB |
Would you care to share any notable or helpful ones?
That being said, does that mean I SHOULD continue to reproduce this reaction and expect a coupling after the 4th or 5th? It's cheap enough in the
short run as I would be using only 15-30mg of the palladium catalyst (probably the most expensive thing here).
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RareEarth
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What kind of Pd catalyst are you using?
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dermolotov
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http://www.sigmaaldrich.com/catalog/product/aldrich/720526?l...
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