Diisopropylethylamine → (S)-2-(tert-butyldiphenylsilyloxy)-1-((R)-5-(2,5-difluorophenyl)-2-((methoxymethoxy)methyl)-2-phenyl-1,3,4-thiadiazol-3(2H)-yl)propan-1-one

HRID 270520Notes

Reaction equation

HRID 270520 reaction equation
[Si:1]([O:18][C@@H:19]([CH3:23])[C:20](O)=[O:21])([C:14]([CH3:17])([CH3:16])[CH3:15])([C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[F:24][C:25]1[CH:30]=[CH:29][C:28]([F:31])=[CH:27][C:26]=1[C:32]1[S:36][C:35]([CH2:43][O:44][CH2:45][O:46][CH3:47])([C:37]2[CH:42]=[CH:41][CH:40]=[CH:39][CH:38]=2)[NH:34][N:33]=1.C1CN([P+](ON2N=NC3C=CC=CC2=3)(N2CCCC2)N2CCCC2)CC1.F[P-](F)(F)(F)(F)F.CCN(C(C)C)C(C)C.C([O-])(O)=O.[Na+]>CN(C=O)C>[Si:1]([O:18][C@@H:19]([CH3:23])[C:20]([N:34]1[N:33]=[C:32]([C:26]2[CH:27]=[C:28]([F:31])[CH:29]=[CH:30][C:25]=2[F:24])[S:36][C@@:35]1([CH2:43][O:44][CH2:45][O:46][CH3:47])[C:37]1[CH:42]=[CH:41][CH:40]=[CH:39][CH:38]=1)=[O:21])([C:14]([CH3:16])([CH3:17])[CH3:15])([C:8]1[CH:9]=[CH:10][CH:11]=[CH:12][CH:13]=1)[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

7

Procedure

To a solution of (S)-2-(tert-butyldiphenylsilyloxy)propanoic acid (0.70 g, 2.14 mmol) in DMF (20 mL) was added 5-(2,5-difluorophenyl)-2-((methoxymethoxy)methyl)-2-phenyl-2,3-dihydro-1,3,4-thiadiazole (0.50 g, 1.43 mmol) followed by PyBOP (1.11 g, 2.14 mmol) and DIEA (497 μL, 2.85 mmol). After stirring at room temperature for 16 hours, the mixture was treated with saturated NaHCO3 (50 mL) and extracted with ethyl acetate (3×30 mL). The combined organics were washed with water (6×30 mL) and brine (30 mL), dried over Na2SO4, and concentrated under reduced pressure. The yellow residue was chromatographed (19:1 to 9:1 hexanes/ethyl acetate) to afford the less polar diastereomer (S)-2-(tert-butyldiphenylsilyloxy)-1-((R)-5-(2,5-difluorophenyl)-2-((methoxymethoxy)methyl)-2-phenyl-1,3,4-thiadiazol-3(2H)-yl)propan-1-one (110 mg, 12%), and the more polar diastereomer (S)-2-(tert-butyldiphenylsilyloxy)-1-((S)-5-(2,5-difluorophenyl)-2-((methoxymethoxy)methyl)-2-phenyl-1,3,4-thiadiazol-3(2H)-yl)propan-1-one (146 mg of a 1:1 mixture with starting material) as yellow oils. Absolute stereochemistry was assigned by inference from (S)-1-((R)-5-(2,5-difluorophenyl)-2-(hydroxymethyl)-2-phenyl-1,3,4-thiadiazol-3(2H)-yl)-2-methoxypropan-1-one.

Workup

  1. extractionextracted with ethyl acetate (3×30 mL)
  2. washThe combined organics were washed with water (6×30 mL) and brine (30 mL)
  3. dry with materialdried over Na2SO4
  4. concentrationconcentrated under reduced pressure
  5. customThe yellow residue was chromatographed (19:1 to 9:1 hexanes/ethyl acetate)

Sources & evidence

ORD record
ord-8d29aed521e34fd0b2d39f598cdfe68d
Source dataset
uspto-grants-2008_11
Patent number
US07449486B2

Reaction notes

Loading…