Synthesis of potassium trifluoroborates

Recent Literature

Arylboronic acids and aryl trifluoroborates are synthesized in a one-pot sequence by Ir-catalyzed borylation of arenes. To prepare the arylboronic acids, the Ir-catalyzed borylation is followed by oxidative cleavage of the pinacol boronates with NaIO₄. To prepare the aryltrifluoroborate, the Ir-catalyzed borylation is followed by displacement of pinacol by KHF₂.
J. M. Murphy, C. C. Tzschucke, J. F. Hartwig, Org. Lett., 2007, 9, 757-760.

The palladium-catalyzed cross-coupling reaction of potassium alkenyltrifluoroborates with aryl and heteroaryl halides and triflates proceeds readily with moderate to excellent yields.
G. A. Molander, C. R. Bernardi, J. Org. Chem., 2002, 67, 8424-8429.

The palladium-catalyzed cross-coupling reaction of potassium alkynyltrifluoroborates with aryl halides or triflates proceeds readily with moderate to excellent yields. The potassium alkynyltrifluoroborates are air- and moisture-stable crystalline solids that can be stored indefinitely, which will provide an advantage in applications to combinatorial chemistry.
G. A. Molander, B. W. Katona, F. Machrouhi, J. Org. Chem., 2002, 67, 8416-8423.

A new synthetic method for the preparation of potassium organotrifluoroborates through nucleophilic substitution of potassium bromo- and iodomethyltrifluoroborates is described. Potassium halomethyltrifluoroborates have been prepared via in situ reaction of n-BuLi with dibromo- and diiodomethane, respectively, in the presence of trialkyl borates, followed by treatment with KHF₂.
G. A. Molander, J. Ham, Org. Lett., 2006, 8, 2031-2034.

Activated pyridine borane complexes (Py·BH₂X) are capable of hydroborating alkenes at room temperature. An unusual hydroboration mechanism is discussed. Hydroboration of alkynes with Py·BH₂I selectively affords the monoadducts. The preparation of synthetically useful potassium alkyltrifluoroborate salts is described.
J. M. Clay, E. Vedejs, J. Am. Chem. Soc., 2005, 127, 5766-5767.

Allyl alcohols were regio- and stereoselectively converted to allyl boronic acids and subsequently to trifluoro(allyl)borates with tetrahydroxy diboron with high isolated yields using palladium pincer-complex catalysis. A mechanism for the fast allylic displacement of a hydroxy group is discussed.
V. J. Olsson, S. Sebelius, N. Selander, K. J. Szabó, J. Am. Chem. Soc., 2006, 128, 4588-4589.

A mild, selective, palladium-catalyzed boronation of vinyl cyclopropane, vinyl aziridine, and allyl acetate substrates could be accomplished using tetrahydroxydiboron in the presence of a palladium pincer complex catalyst to give synthetically useful linear trifluoro(allyl)borates or allyl boronates incorporating a trans double bond. Functionalities such as Br, COOEt, ArSO₂(NH), OAc, and SiRMe₂ are tolerated.
S. Sebelius, V. J. Olsson, K. J. Szabó, J. Am. Chem. Soc., 2005, 127, 10478-10479.

S. Sebelius, V. J. Olsson, K. J. Szabó, J. Am. Chem. Soc., 2005, 127, 10478-10479.

3-Substituted-2-alkoxycarbonyl allylboronates are readily produced by the cross-coupling of Baylis-Hillman acetate adducts and bis(pinacolato)diboron in the presence of a palladium catalyst. Subsequent addition of excess aqueous KHF₂ gives stable allyl trifluoroborate salts. Allylboronate and allyltrifluoroborate derivatives react stereoselectively with aldehydes to afford functionalized homoallylic alcohols.
G. W. Kabalka B. Venkataiah, G. Dong, J. Org. Chem., 2004, 69, 5807-5809.

Related:

A new synthetic method for the preparation of potassium organotrifluoroborates through nucleophilic substitution of potassium bromo- and iodomethyltrifluoroborates is described. Potassium halomethyltrifluoroborates have been prepared via in situ reaction of n-BuLi with dibromo- and diiodomethane, respectively, in the presence of trialkyl borates, followed by treatment with KHF₂.
G. A. Molander, J. Ham, Org. Lett., 2006, 8, 2031-2034.

The cis-dihydroxylation of olefin-containing potassium alkyl- and aryltrifluoroborates proceeds readily in moderate to excellent yields. The resulting diols are efficient coupling partners in Suzuki-Miyaura-type reactions with both alkenyl and aryl bromides.
G. A. Molander, R. Figueroa, Org. Lett., 2006, 8, 75-78.

1-Trifluoroboratoalkenes are oxidized by dioxirane, providing air-stable, crystalline oxiranyltrifluoroborates without cleavage of the carbon-boron bond. The first Suzuki-Miyaura coupling of an epoxytrifluoroborate has been accomplished.
G. A. Molander, M. Ribagorda, J. Am. Chem. Soc., 2003, 125, 11148-11149.