ChemicalBook CAS DataBase List 2-Tolylboronic acid

2-Tolylboronic acid synthesis

14synthesis methods

Product Name:2-Tolylboronic acid
CAS Number:16419-60-6
Molecular formula:C7H9BO2
Molecular Weight:135.96

Triphenylphosphene (0.131 g, 0.5 mmol, 20 mol %), p-iodoanisol (0.585 g, 2.5 mmol), and triethylamine (1.78 mL, 12.5 mmol) were added to a 50 mL round-bottomed flask equipped with a sidearm, condenser, and stir bar. This solution was then degassed by alternating vacuum and argon three times. Palladium dichloride (0.023 g, 0.13 mmol, 5 mol %) was then added under positive argon pressure. After stirring at room temperature for 15 min, diisopropylaminoborane (5 mL, 1 M solution in THF, 5 mmol) was added and the reaction mixture was degassed again by alternating vacuum and argon three times. The reaction solution was then heated to reflux. After 12 h of reflux the reaction was cooled to 0 °C and 6 mL of methanol was added through the condenser slowly (Caution: exothermic reaction with evolution of hydrogen). After 15 min of stirring all the solvent was removed under reduced pressure to yield a black solid. This solid was dissolved with sodium hydroxide (3 M, 8 mL) and subsequently washed with hexanes (3×10 mL). The aqueous layer was then cooled to 0 °C (ice bath) and acidified to pH ≤1 with concentrated HCl, with the boronic acid usually precipitating out as a white solid. The aqueous fraction was then extracted with diethyl ether (3×10 mL). The organic fractions were combined, dried with magnesium sulfate and filtered. The solvent was then removed under reduced pressure yielding a white solid named 2-Tolylboronic acid.

95-49-8 Synthesis

95-49-8
337 suppliers
$10.00/5g

605-39-0 Synthesis

605-39-0
104 suppliers
$19.00/1g

16419-60-6
378 suppliers
$9.00/1g

Yield:16419-60-6 97%

Reaction Conditions:

with cesium fluoride;Pd(dba)2 in toluene;

Steps:

5 Example 5

Example 5 This is an example of Pd/ligand 1-catalyzed Suzuki reaction for biaryl synthesis 2,2'-Dimethyl-1,1'-biphenyl The title compound was obtained as a yellowish oil (180 mg, 97% isolated yield) from the reaction of 2-methyl-phenylboronic acid (203 mg, 1.54 mmol), CsF (469 mg, 3.09 mmol), Pd(dba)₂ (11.8 mg, 21 μmol), ligand 1 (22 mg, 61 μmol), and 2-chlorotoluene (0.12 mL, 1.03 mmol) in toluene (4 mL) at 110° C. for 5 h. TON=49 and TOF=9.8. ¹ H NMR (CDCl₃): δ7.32-7.18 (m, 6H, ArH), 7.13 (d, J=6.2, 2H, ArH), 2.08 (s, 6H, CH₃'s). ¹³C{¹H} NMR (CDCl₃): δ141.6, 135.8, 129.8, 129.3, 127.1, 125.5, 19.8.

References:

US6268513,2001,B1

95-46-5 Synthesis