Tetrabutylammonium Fluoride → 4-((1R,2S)-1-(5-(4-cyanophenyl)-1,3,4-oxadiazol-2-yl)-2-hydroxypropylamino)benzo[b]thiophene-7-carbonitrile

HRID 2388516Notes

Reaction equation

HRID 2388516 reaction equation
[Si]([O:8][C@@H:9]([CH3:36])[C@@H:10]([NH:24][C:25]1[C:33]2[CH:32]=[CH:31][S:30][C:29]=2[C:28]([C:34]#[N:35])=[CH:27][CH:26]=1)[C:11]1[O:12][C:13]([C:16]2[CH:21]=[CH:20][C:19]([C:22]#[N:23])=[CH:18][CH:17]=2)=[N:14][N:15]=1)(C(C)(C)C)(C)C.CCCC[N+](CCCC)(CCCC)CCCC.[F-]>C1COCC1>[C:22]([C:19]1[CH:20]=[CH:21][C:16]([C:13]2[O:12][C:11]([C@H:10]([NH:24][C:25]3[C:33]4[CH:32]=[CH:31][S:30][C:29]=4[C:28]([C:34]#[N:35])=[CH:27][CH:26]=3)[C@@H:9]([OH:8])[CH3:36])=[N:15][N:14]=2)=[CH:17][CH:18]=1)#[N:23]

Participants

4

Procedure

To a solution of 4-((1R,2S)-2-(tert-butyldimethylsilyloxy)-1-(5-(4-cyanophenyl)-1,3,4-oxadiazol-2-yl)propylamino)benzo[b]thiophene-7-carbonitrile (355 mg, 0.69 mmol) in THF (33 mL) was added TBAF (0.70 mL, 0.70 mmol, 1 M solution in THF) at −50° C. After addition, the reaction mixture was stirred between −30° C. to −50° C. for 2 h, then quenched by adding saturated aqeuous NH4Cl solution (10 mL) and extracted with EtOAc. The EtOAc extracts were washed with water, brine, dried over Na2SO4. The solvent was removed to provide a residue, which was subjected to flash chromatography purification to give the title compound 4-((1R,2S)-1-(5-(4-cyanophenyl)-1,3,4-oxadiazol-2-yl)-2-hydroxypropylamino)benzo[b]thiophene-7-carbonitrile (173 mg, 63%) and some dehydration product 4-(1-(5-(4-cyanophenyl)-1,3,4-oxadiazol-2-yl)prop-1-enylamino)benzo[b]thiophene-7-carbonitrile (70 mg, 27%). Title compound: 1H NMR (400 MHz, Acetone-d6, δ in ppm) 8.16 (d, J=8.8 Hz, 2H), 7.95 (d, J=8.8 Hz, 2H), 7.87 (d, J=5.7 Hz, 1H), 7.72 (d, J=5.7 Hz, 1H), 7.62 (d, J=8.2 Hz, 1H), 6.83 (d, J=8.2 Hz, 1H), 6.48 (d, J=8.6 Hz, 1H), 5.25 (dd, J=4.3, 8.6 Hz, 1H), 4.79 (b, 1H), 4.66 (m, 1H), 1.42 (d, J=6.3 Hz, 3H). Dehydration product: 1H NMR (400 MHz, Acetone-d6, δ in ppm) 8.25 (d, J=8.2 Hz, 2H), 8.01 (d, J=8.2 Hz, 2H), 7.96 (d, J=5.5 Hz, 1H), 7.81 (d, J=5.5 Hz, 1H), 7.61 (d, J=8.2 Hz, 1H), 7.09 (q, J=7.0 Hz, 1H), 6.58 (d, J=8.2 Hz, 1H), 1.95 (d, J=7.0 Hz, 3H).

Workup

  1. additionAfter addition
  2. customquenched
  3. additionby adding saturated aqeuous NH4Cl solution (10 mL)
  4. extractionextracted with EtOAc
  5. washThe EtOAc extracts were washed with water, brine
  6. dry with materialdried over Na2SO4
  7. customThe solvent was removed
  8. customto provide a residue, which
  9. customwas subjected to flash chromatography purification

Sources & evidence

ORD record
ord-c1fcea30405c475f87afda2068f11d79
Source dataset
uspto-grants-2012_09
Patent number
US08268872B2

Reaction notes

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