(2S,3S,alphaS)-t-Butyl 3-(N-allyl-alpha-methylbenzylamino)-2-hydroxy-3-phenylpropionate → (2S,4S,5S,alphaS)-2-Ethyl-3-(alpha-methylbenzyl)-4-phenyl-1,3-oxazolidine-5-carboxylic acid t-butyl ester

HRID 1637047Notes

Reaction equation

HRID 1637047 reaction equation
[CH2:1]([N:4]([C@@H:21]([CH3:28])[C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1)[C@@H:5]([C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1)[C@H:6]([OH:14])[C:7]([O:9][C:10]([CH3:13])([CH3:12])[CH3:11])=[O:8])[CH:2]=[CH2:3]>C1(C)C=CC=CC=1.[Rh]Cl.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>[C:10]([O:9][C:7]([C@H:6]1[O:14][C@@H:1]([CH2:2][CH3:3])[N:4]([C@@H:21]([CH3:28])[C:22]2[CH:23]=[CH:24][CH:25]=[CH:26][CH:27]=2)[C@H:5]1[C:15]1[CH:16]=[CH:17][CH:18]=[CH:19][CH:20]=1)=[O:8])([CH3:13])([CH3:12])[CH3:11]

Participants

4

Reactant 1

HCID 86755227(2S,3S,alphaS)-t-Butyl 3-(N-allyl-alpha-methylbenzylamino)-2-hydroxy-3-phenylpropionate

Product 1

HCID 86755235(2S,4S,5S,alphaS)-2-Ethyl-3-(alpha-methylbenzyl)-4-phenyl-1,3-oxazolidine-5-carboxylic acid t-butyl esterYield 83%

Reagents, catalysts & solvents 2

HCID 178479813HCID 178479813, compoundCatalystHCID 1140TolueneSolvent2×

Procedure

To a solution of compound (27) from Example 12 (1.039 g, 2.73 mmol) in anhydrous toluene (25 ml) was added tris(triphenylphosphine) rhodium(I) chloride (126 mg, 5 mol %). This solution was refluxed for 4 hours whereafter the toluene was removed under reduced pressure. The residue was treated with diethyl ether, precipitating the catalyst, and the solution was passed through alumina grade 5. After removal of the solvent under reduced pressure, the resulting oil was purified by flash chromatography on silica gel [ethyl acetate/petroleum ether (1:19)] affording the title compound (Rf 0.40) as a colourless oil (0.86 g, 83%). δH (300 MHz; CDCl3) 7.33-7.18 (10H, m, Ph), 4.48 (1H, t, NCHO), 4.38 (1H, d, J=8.0, PhCHCH), 4.21 (1H, d, J=8.0, PhCHCH), 4.01 (1H, q, J=6.9, PhCHCH3), 1.91 (2H, m, CHCH2CH3), 1.27 (3H, d, J=6.9, PhCHCH3), 1.15 (3H, t, J=7.5, CHCH2CH3), 0.99 (9H, s, (CH3)3C).

Workup

  1. customwas removed under reduced pressure
  2. additionThe residue was treated with diethyl ether
  3. customprecipitating the catalyst
  4. customAfter removal of the solvent under reduced pressure
  5. customthe resulting oil was purified by flash chromatography on silica gel [ethyl acetate/petroleum ether (1:19)]

Sources & evidence

ORD record
ord-ad151db2dfb64c179edb4f15a00b19e2
Source dataset
uspto-grants-2000_03
Patent number
US06037498

Reaction notes

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