5-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)pyridin-2-amine

equipped with a mechanical stirring in a 5L three flask, 300g2--amino-5-bromopyridine, 528 g of boronic acid pinacol ester-linked, 3L1, 4- dioxane, 42.4gPd (dppf)A different strategy was designed using 5-pyridyl boronate and subsequently oxidized to P5 in the presence OfNaOCH10167] 5-(4, 4, 5, 5-tetramethyl-1 , 3, 2-dioxaborolan-2-yl)pyridin-2 -amine, made in laboratory. The preparation methodwas as follows:10168] 2-amino-5-bromopyridine (5.1 g, 30 mmol), bis(pinacolato)diboron (10.7 g, 45 mmol), potassium carbonate(8.3 g, 60 mmol), and tetrakis(triphenylphosphine)palladium(693 mg, 0.6 mmol) were added to 150 mL dioxane and 2 mLwater. The resulting mixture was reacted under reflux in thenitrogen protection for 4 hours, cooled to room temperature, filtered and concentrated. The crude product was dissolved in300 mL dichioromethane, washed with water, dried overanhydrous sodium sulfate, and concentrated. When only asmall amount of solvent retained, petroleum ether was addedthereto. A yellow solid was separated out and filtered to obtaina product (1.8 g).Under nitrogen protection, 550 mL of dioxane and 2-nitro-5-bromopyridine (20.3 g, After 0.10 mol) of pinacol borate (25.4 g, 0.10 mol) and potassium acetate (14.7 g, 0.15 mol), after stirring uniformly, the catalyst PdCl2dppf (0.74 g, 0.001 mol) was finally added, and the temperature was slowly raised to 80- 90 °C, Stir the reaction for 2-3 h. After the completion of the GC reaction, the reaction was stopped by cooling, and the reaction solution was filtered through celite to obtain a dark-black reaction solution. After charging at 1 atm of hydrogen, the mixture was reacted at room temperature overnight. After the reaction was completed, the activated carbon was decolorized, and the filtrate was distilled under reduced pressure until no liquid was poured. /Heptane mixed solvent was cooled and beaten for half an hour, filtered to obtain 18.5 g of light gray product, heated again with ethanol, and then cooled down, and the filter cake was rinsed with -20 ° C anhydrous ethanol, and dried to obtain 16.9 g, yield 77 percent HPLC purity 99.6percent

Substrate used in a microwave-assisted, four-component coupling process leading to amino substituted imidazopyridines.1

Molecular Weight:220.08
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:4
Rotatable Bond Count:1
Exact Mass:220.1383080
Monoisotopic Mass:220.1383080
Topological Polar Surface Area:57.4
Heavy Atom Count:16
Complexity:255
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes