Newsletter N° 16 - March 2011

Contents :  Potassium trifluoroborates

Focus on potassium trifluoroborates

Once again we will talk about trifluoroborates as there is major news!

Trifluoroborates have been an amazing success but their scale-up pointed out structural anomalies. The BoroChem team was the first to warn you about this problem in our 12th newsletter. The answer to this issue came from the Molander's team who gave us a preview of the following information as part of our Scientific Board.

The article soon be published ⁽¹⁾ but results are already available here.

To summarize, aminomethyltrifluoroborates are not free bases, but internal salts (zwitterionic ammoniomethyltrifluoroborates with small amounts of KBr) :

The products keep their amazing possibilities, especially in Suzuki cross-couplings.



Their characteristics remain quite similar and the usefulness of those building blocks has been proven beyond doubts, so you will still find them at unchanged prices in our product list with corrected names, structures, and formulas as follows (other  compounds remain unchanged):

Structure	Name	Référence	New structure	New name
	Potassium (piperidin -1-yl) methyl trifluoroborate	BF1-0002		(Piperidinium-1-ylmethyl) trifluoroborate Internal salt
	Potassium N-tert-butyl- aminomethyl trifluoroborate	BF1-0003		[(tert- butylammonium) methyl] trifluoroborate Internal salt
	Potassium N- cyclohexyl- aminomethy ltrifluoroborate	BF1-0005		[(cyclohexyl ammonium) methyl] trifluoroborate Internal salt
	Potassium (morpholin-4-yl) methyl trifluoroborate	BF1-0006		(Morpholinium-4-ylmethyl) trifluoroborate Internal salt
	Potassium N-benzyl- N-methyl- aminomethyl trifluoroborate	BF1-0007		[(N-benzyl- N-methyl- ammonium) methyl] trifluoroborate Internal salt
	Potassium (4-tert- butoxycarbonyl piperazin-1-yl) methyl trifluoroborate	BF1-0008		[(4-tert- butoxycarbonyl piperazin -1-ium-1-yl) methyl] trifluoroborate Internal salt
	Potassium N-cyclohexyl -N-methyl- aminomethyl trifluoroborate	BF1-0009		[(N-cyclohexyl- N-methyl- ammonium) methyl] trifluoroborate Internal salt
	Potassium (4- methylpiperazin -1-yl) methyl trifluoroborate	BF1-0013		[(4-methylpiperazin-1-ium-1yl) methyl] trifluoroborate Internal salt
	Potassium (pyrrolidin-1-yl) methyl trifluoroborate	BF1-0014		[(Pyrrolidinium) methyl] trifluoroborate Internal salt
	Potassium (thiomorpholin -4-yl) methyl trifluoroborate	BF1-0015		(Thiomorpholinium-4-ylmethyl) trifluoroborate Internal salt
	Potassium dimethyl aminomethyl trifluoroborate	BF1-0016		[(dimethyl ammonium) methyl] trifluoroborate Internal salt

As a reminder, do not forget that organoboronated salts are a serious alternative to boronic acids.

For example, you can avoid contamination of boronic acid by boroxine by using:

	instead of		containing varying amounts of anhydride
B01-0105		B01-0001

(1) Reinvestigation of Aminomethyltrifluoroborates and Their Application in Suzuki-Miyaura Cross-Coupling Reactions, Raushel, J.; Sandrock, DL.; Josyula, KV.; Pakyz, D.; Molander, GA. ; J. Org. Chem, 2011, ASAP