2-Hydrazinopyridine

White to light beige low melting solid

Synthesis of pyridin-2-yl-hydrazine (2): To a stirredsolution of 1 (20 g, 0.176 mol, 1 equiv) in hydrazine hydrate (200 mL, 10 vol) was stirred at 100 °C for 48 h. When TLC (8:2 EtOAc and methanol) showed complete consumption of the starting material, the reaction mixture was diluted with water (200 mL) and extracted with ethyl acetate (5 × 500 mL), dried over Na2SO4 evaporated to dryness under reduced pressure to afford 2 (15.0 g, 78 percent) as a red oil; 1H NMR (300 MHz, CDCl3): δ 8.14 (1H, d, J = 3 Hz, Ar-H), 7.51-7.45 (1H, m, Ar-H), 6.71-6.66 (2H, m, Ar-H), 5.78 (1H, brs, -NH), 3.81 (2H, brs, -NH2); LCMS calculated for C5H7N3: 109.13; Found 110.1, [M+H]+Hydrazine monohydrate (13.22 g, 12.8 mL, 264.2 mmol) was added to 2-chloropyridine (3 g, 2.5 mL, 26.42 mmol) in a two necked round-bottom flask. The resultinghomogeneous mixture was refluxed for 6 h under argon atmosphere. Then it was allowed tocome to room temperature and extracted with Et2O three times before the remaining aqueouslayer was evaporated under reduced pressure. Water (60 mL) and solid KOH (3 g) was thenadded and resulting mixture was further extracted with diethyl ether (4 x 15 mL). Finally thereaction mixture was washed with brine, dried over anhydrous Na2SO4 and titled compoundwas afforded as brown low melting solid by solvent removal under reduced pressure (1.96 g, 68percent).Step 1: 2-hydrazinylpyridine [0276] 2-Chloropyridine (3.0 mL, 32 mmol) was mixed with hydrazine hydrate (15 mL), and the mixture was heated under reflux. After stirring overnight, the reaction was cooled to room temperature. The solvent was evaporated to afford the title compound as a yellow oil (2.1 g, 61percent). MS (ESI) calcd for C5H7N3: 109.1; found: 110.2 [M+H]. *H NMR (400 MHz, CDCIOne mmol liquid 2-chloropyridine was dissolved in 2.0 mL 85percent hydrazine hydrate and methanol (5 mL) and the mixture was refluxed at 90 °C for 6 h upon cooling, a yellow solid was separated out and recrystallized with ethanol-DMF to get the pure 2-hydrazinopyridine. Yield 60percent.2-hydrazopyridine

Molecular Weight:109.13
XLogP3:0.3
Hydrogen Bond Donor Count:2
Hydrogen Bond Acceptor Count:3
Rotatable Bond Count:1
Exact Mass:109.063997236
Monoisotopic Mass:109.063997236
Topological Polar Surface Area:50.9
Heavy Atom Count:8
Complexity:64.7
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes