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The mechanism of organotrifluoroborate-based Suzuki-Miyaura coupling reactions has recently been investigated in detail. The organotrifluoroborate hydrolyses to the corresponding boronic acid in situ, so a boronic acid can be used in place of an organotrifluoroborate, as long as it is added slowly and carefully. [7] [8]
Potassium fluoroborate is obtained by treating potassium carbonate with boric acid and hydrofluoric acid. B(OH) 3 + 4 HF → HBF 4 + 3 H 2 O 2 HBF 4 + K 2 CO 3 → 2 KBF 4 + H 2 CO 3. Fluoroborates of alkali metals and ammonium ions crystallize as water-soluble hydrates with the exception of potassium, rubidium, and cesium.
The first to investigate trifluoromethyl groups in relationship to biological activity was F. Lehmann in 1927. [5] An early review appeared in 1958. [6] An early synthetic method was developed by Frédéric Swarts in 1892, [7] based on antimony fluoride. In this reaction benzotrichloride was reacted with SbF 3 to form PhCF 2 Cl and PhCF 3.
Potassium tetraphenylborate is the salt with the formula KB(C 6 H 5) 4). It is a colourless salt that is a rare example of a water-insoluble salt of potassium. The salt has a low solubility in water of only 1.8×10 −4 g/L. It is, however, soluble in organic solvents.
The [BAr F 4] − anion with four fluorinated aryl groups distributed tetrahedrally about a central boron atom. Tetrakis[3,5-bis(trifluoromethyl)phenyl]borate is an anion with chemical formula [{3,5-(CF 3) 2 C 6 H 3} 4 B] −, which is commonly abbreviated as [BAr F 4] −, indicating the presence of fluorinated aryl (Ar F) groups.
Potassium trifluoroacetate can be obtained by reacting trifluoroacetic acid with potassium hydroxide, potassium carbonate or potassium bicarbonate. CF 3 COOH + KOH → CF 3 COOK + H 2 O. It can decompose when heated and reaches the maximum decomposition rate at 220 °C.
According to the American Cancer Society, these rates have risen by 2% annually since 2011. “Early onset colorectal cancer (colon cancer in persons under age 50) is on the rise, but in absolute ...
3,4-Dichlorophenol 3,5-Dichlorophenol Dichlorophenols are used as intermediates in the manufacture of more complex chemical compounds, including the common herbicide 2,4-dichlorophenoxyacetic acid (2,4-D).