tert-Butyl carbazate → 5-(2-Chloro-6-methylpyridin-4-yl)-3-methyl-1,3,4-oxadiazol-2(3H)-one

HRID 1056610Notes

Reaction equation

HRID 1056610 reaction equation
C(O[C:6]([NH:8][NH:9][C:10](=[O:19])[C:11]1[CH:16]=[C:15]([CH3:17])[N:14]=[C:13]([Cl:18])[CH:12]=1)=[O:7])(C)(C)C.Cl[C:21]1C=C(C=C(C)N=1)C(O)=O.N(C(OC(C)(C)C)=O)N.CN(C(ON1N=NC2C=CC=CC1=2)=[N+](C)C)C.[B-](F)(F)(F)F.CCN(C(C)C)C(C)C>CN(C=O)C.C(OCC)(=O)C.O>[Cl:18][C:13]1[CH:12]=[C:11]([C:10]2[O:19][C:6](=[O:7])[N:8]([CH3:21])[N:9]=2)[CH:16]=[C:15]([CH3:17])[N:14]=1

Participants

9

Reactant 5

HCID 70091tert-Butyl carbazateHCID 81531DiisopropylethylamineHCID 1412092-Chloro-6-methylpyridine-4-carboxylic acidHCID 2733207O-(Benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborateHCID 122621219t-Butyl-2-(2-chloro-6-methylisonicotinoyl)hydrazinecarboxylate

Product 1

HCID 900105625-(2-Chloro-6-methylpyridin-4-yl)-3-methyl-1,3,4-oxadiazol-2(3H)-oneYield 45%

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 6228DimethylformamideSolventHCID 8857Ethyl AcetateSolvent

Procedure

Step-1: t-Butyl-2-(2-chloro-6-methylisonicotinoyl)hydrazinecarboxylate: To a stirred solution of 2-chloro-6-methylisonicotinic acid (4.0 g, 23.3 mmol) in DMF (40 mL) was added successively tert-butyl hydrazine carboxylate (3.0 g, 23.3 mmol), TBTU (6.0 g, 18.6 mmol) and DIPEA (12.2 mL, 69.9 mmol). After stirring for 12 hat RT, water (20 mL) was added to the reaction followed by ethyl acetate (50 mL). The layers were separated and the aqueous layer was extracted with ethyl acetate (3×50 mL). The combined organic layers were washed with brine (50 mL), dried (Na2SO4) and filtered. The filtrate was concentrated under vacuum to afford 3.0 g (45%) of the title compound as white solid. 1HNMR (400 MHz, CDCl3) δ 8.65 (s, D2O exchangeable, 1H), 7.48 (s, 1H), 7.42 (s, 1H), 6.77 (s, D2O exchangeable, 1H), 2.59 (s, 3H), 1.53 (s, 9H); GC-MS (m/z) 185 (M)+

Workup

  1. additionwas added to the reaction
  2. customThe layers were separated
  3. extractionthe aqueous layer was extracted with ethyl acetate (3×50 mL)
  4. washThe combined organic layers were washed with brine (50 mL)
  5. dry with materialdried (Na2SO4)
  6. filtrationfiltered
  7. concentrationThe filtrate was concentrated under vacuum

Sources & evidence

ORD record
ord-9f9a3496de264abfbb2a944a5de67b00
Source dataset
uspto-grants-2016_07
Patent number
US09399638B2

Reaction notes

Loading…