Potassium Carbonate → N-(2-hydroxytetrahydro-2H-pyran-4-yl)-[2,1,3]-benzoxadiazole-5-carboxamide

HRID 238557Notes

Reaction equation

HRID 238557 reaction equation
NC(CCO)CCO.N1ON=C2C=C(C(Cl)=O)C=CC=12.C(=O)([O-])[O-].[K+].[K+].[OH:27][CH2:28][CH2:29][CH:30]([NH:34][C:35]([C:37]1[CH:45]=[CH:44][C:40]2=[N:41][O:42][N:43]=[C:39]2[CH:38]=1)=[O:36])[CH2:31][CH2:32][OH:33].CC(OI1(OC(C)=O)(OC(C)=O)OC(=O)C2C=CC=CC1=2)=O>ClCCl.C(Cl)(Cl)Cl.CO.C(N(CC)CC)C>[OH:27][CH:28]1[CH2:29][CH:30]([NH:34][C:35]([C:37]2[CH:45]=[CH:44][C:40]3=[N:41][O:42][N:43]=[C:39]3[CH:38]=2)=[O:36])[CH2:31][CH2:32][O:33]1

Participants

10

Reactant 5

HCID 11430Potassium CarbonateHCID 159087TriacetoxyperiodinaneHCID 27354532,1,3-Benzoxadiazole-5-carbonyl chlorideHCID 211178053-Aminopentane-1,5-diolHCID 66725669N-(1,5-dihydroxypentan-3-yl)-[2,1,3]-benzoxadiazole-5-carboxamide

Product 1

HCID 25104754N-(2-hydroxytetrahydro-2H-pyran-4-yl)-[2,1,3]-benzoxadiazole-5-carboxamideYield 24%

Reagents, catalysts & solvents 4

HCID 887MethanolSolventHCID 6212ChloroformSolventHCID 6344DichloromethaneSolvent2×HCID 8471TriethylamineSolvent

Conditions

Temperature
45 °C

Procedure

To a solution of 3-aminopentane-1,5-diol (2.38 g, 20 mmol) (Helv. Chim. Acta 1964, 47(8), 2145-2153) and triethylamine (4 ml), in dichloromethane (30 ml), was slowly added, at 0° C., a solution of [2,1,3]-benzoxadiazole-5-carboxylic acid chloride (1.82 g, 10 mmol), in dichloromethane (20 ml), and the mixture stirred for 1 h. A mixture of methanol (30 ml) and 4N potassium carbonate solution (20 ml) was added and stirred for 3 h. The mixture was evaporated onto silica gel and purified by silica gel chromatography eluting with ethyl acetate/chloroform/methanol (60:30:10) to give, after crystallization from dichloromethane/ethyl acetate/diethyl ether, N-(1,5-dihydroxypentan-3-yl)-[2,1,3]-benzoxadiazole-5-carboxamide as a white solid (Mp: 87-88° C.). N-(1,5-Dihydroxypentan-3-yl)-[2,1,3]-benzoxadiazole-5-carboxamide (0.5 g, 1.9 mmol), suspended in chloroform (20 ml), was warmed to 45° C. and periodinane (Dess Martin reagent; 1.6 g) added and stirred for 1 h. The reaction mixture was evaporated onto silica gel and purified by chromatography, eluting with ethyl acetate/chloroform (60:40) to give N-(2-hydroxytetrahydro-2H-pyran-4-yl)-[2,1,3]-benzoxadiazole-5-carboxamide (0.12 g) as a white solid after trituration with diethyl ether and as the less polar of two components (Rf: 0.55). Mp=91-92° C., 1H NMR (300 MHz, CDCl3) δ 8.22 (s, 1H); 7.96-7.81 (m, 2H); 7.10-7.00 and 6.40-6.05 (m, 2H); 4.65-4.40 (m, 1H); 4.15-3.70 (m, 2H) and 2.15-0.60 ppm (m, 4H).

Workup

  1. additionwas added
  2. customThe mixture was evaporated onto silica gel
  3. custompurified by silica gel chromatography
  4. washeluting with ethyl acetate/chloroform/methanol (60:30:10)
  5. customto give
  6. customafter crystallization from dichloromethane/ethyl acetate/diethyl ether, N-(1,5-dihydroxypentan-3-yl)-[2,1,3]-benzoxadiazole-5-carboxamide as a white solid (Mp: 87-88° C.)
  7. stirringstirred for 1 h
  8. customThe reaction mixture was evaporated onto silica gel
  9. custompurified by chromatography
  10. washeluting with ethyl acetate/chloroform (60:40)

Sources & evidence

ORD record
ord-5bcd8f5b995649dbbf183835db538685
Source dataset
uspto-grants-2014_02
Patent number
US08642633B2

Reaction notes

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