2-(BocaMino)pyridine-4-boronic acid pinacol ester

Preparation 24terf-Butyl (4-bromopyhdin-2-yl)carbannate (0.494 g, 1 .81 mmol), bis(pinacolato)diboron (1 .4 g 5.51 mmol ) and potassium acetate (0.535 g , 5.45 mmol) were stirred in dimethylsulfoxide (8 ml_). The mixture was flushed with nitrogen for 10 minutes. [1 , 1 '- Bis(diphenylphosphino)ferrocene] dichloropalladium(ll) (0.150 g, 0.184 mmol) was added and the system flushed for a further 5 minutes with nitrogen before heating the reaction mixture to 85A solution of intermediate 20b (352 mg), potassium acetate (380 mg), 4, 4, 4′, 4′, 5, 5, 5′, 5′-octamethyl-2, 2′-bi(1, 3, 2-dioxaborolane) (360 mg) and Pd(dppf)ClIntermediate 20c) A solution of intermediate 20b (352 mg), potassium acetate (380 mg), 4, 4, 4', 4', 5, 5, 5', 5'-octamethyl-2, 2'- bi(1 , 3, 2-dioxaborolane) (360 mg) and Pd(dppf)CIStep 6.1. 2-Ammopyndmc-4-boromc acid pinacol cstcr (2 0 g 9 1 rnmol) was siirrcd as asuspension in ret t-hutanol 30 mL) undei an aigon atinosphete The Boc anhydride (2 20g, 10.0 mmol) in tert-butanoi (20 mL) was added slowly, and the reaction stirred at 35 °Cfor 18 hours. Analysis by H N MR showed the pinacol ester starting material had beenconsumed. The reaction mixture was concentrated under reduced pressure, and the crudematerial stirred in water fur 5 minutes. The solid was collected by filtration and dried in vacuo at 50 °C. to afford tert-hutyl 4-(4, 4, 5, 5-tetramethy1- i , 3, 2-dioxaborolan-2- yi)pyridin-2-yl)carbamate (31) as a white solid (2.9 g, 98percent); mp 172— 178.0°C.(Lit. 188193 °C). 1H NMR (200 MHz, DMSO-d6) 8 9.75 (hr s, lEO, 8.26 (di 1 H, J 0.9, 4.8 Hz), 808(ni lH)., 7 l8dd 111 J07 4 8Hz), 147(s 911) 131 (s 1211)

Molecular Weight:320.2
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:5
Rotatable Bond Count:4
Exact Mass:320.1907374
Monoisotopic Mass:320.1907374
Topological Polar Surface Area:69.7
Heavy Atom Count:23
Complexity:432
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes