Triethylamine → (5-tert-Butyl-[1,3,4]oxadiazol-2-yl)-carbamic acid 2,2,2-trichloro-ethyl ester

HRID 75575Notes

Reaction equation

HRID 75575 reaction equation
[C:1]([C:5]1[O:9][C:8]([NH2:10])=[N:7][N:6]=1)([CH3:4])([CH3:3])[CH3:2].CCN(CC)CC.Cl[C:19]([O:21][CH2:22][C:23]([Cl:26])([Cl:25])[Cl:24])=[O:20]>CC#N>[Cl:24][C:23]([Cl:26])([Cl:25])[CH2:22][O:21][C:19](=[O:20])[NH:10][C:8]1[O:9][C:5]([C:1]([CH3:4])([CH3:3])[CH3:2])=[N:6][N:7]=1

Participants

5

Reactant 3

HCID 8471TriethylamineHCID 870632,2,2-Trichloroethyl chloroformateHCID 133813935-tert-Butyl-1,3,4-oxadiazol-2-amine

Product 1

HCID 86686684(5-tert-Butyl-[1,3,4]oxadiazol-2-yl)-carbamic acid 2,2,2-trichloro-ethyl esterYield 73.3%

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Procedure

To a suspension of 5-tert-butyl-[1,3,4]oxadiazol-2-ylamine (Atlantic, 141 mg, 1.00 mmol) and Et3N (279 μL, 2.00 mmol) in MeCN (2 mL), 2,2,2-trichloroethyl chloroformate (207 μL, 1.50 mmol) was added in 4 portions over 1 min at RT (CARE: exotherm to ˜40° C.). The resulting suspension was stirred for 1 h. The suspension was filtered, washing the solid with MeCN (3 mL), and concentrated to leave a yellow-brown paste. Purification by FCC, using 0-2.5% MeOH in DCM, gave a buff foam (232 mg, 73%). 1H NMR (400 MHz, CDCl3): 1.42 (9H, s), 4.86 (2H, s).

Workup

  1. additionwas added in 4 portions over 1 min at RT (CARE: exotherm to ˜40° C.)
  2. filtrationThe suspension was filtered
  3. washwashing the solid with MeCN (3 mL)
  4. concentrationconcentrated
  5. customto leave a yellow-brown paste
  6. customPurification by FCC

Sources & evidence

ORD record
ord-4a0c049e2c9440fbaf1c88a60bf9bf59
Source dataset
uspto-grants-2014_09
Patent number
US08835431B2

Reaction notes

Loading…