Dimethyl Sulfoxide → 5-Formyl-2(S)-phthalimidopentanoic acid

HRID 543207Notes

Reaction equation

HRID 543207 reaction equation
[OH:1][CH2:2][CH2:3][CH2:4][CH2:5][C@H:6]([N:10]1[C:14](=[O:15])[C:13]2=[CH:16][CH:17]=[CH:18][CH:19]=[C:12]2[C:11]1=[O:20])[C:7]([OH:9])=[O:8].[Cr](O[Cr]([O-])(=O)=O)([O-])(=O)=O.[NH+]1C=CC=CC=1.[NH+]1C=CC=CC=1.C1COCC1.CS(C)=O>C(Cl)Cl.N1C=CC=CC=1>[CH:2]([CH2:3][CH2:4][CH2:5][C@H:6]([N:10]1[C:11](=[O:20])[C:12]2=[CH:19][CH:18]=[CH:17][CH:16]=[C:13]2[C:14]1=[O:15])[C:7]([OH:9])=[O:8])=[O:1]

Participants

7

Reactant 4

HCID 679Dimethyl Sulfoxide2×HCID 8028TetrahydrofuranHCID 2724130Cornforth reagentHCID 11065730(S)-2-Phthalimido-6-hydroxyhexanoic acid

Product 1

HCID 132416335-Formyl-2(S)-phthalimidopentanoic acid

Reagents, catalysts & solvents 2

HCID 1049PyridineSolventHCID 6344DichloromethaneSolvent

Procedure

6-Hydroxy-2(S)-phthalimidohexanoic acid (1.94 g) was dissolved in 145 ml of CH2Cl2 containing 2.26 ml of pyridine. Pyridinium dichromate (1.95 g) was added and the mixture stirred overnight under nitrogen. By addition to 200 ml of ethyl acetate and filtration, chromium salts were removed. The filtrate was concentrated under vacuum. The residue was redissolved in 250 ml of ethyl acetate and the solution refiltered. The filtrate was finally passed through a MgSO4 pad to remove trace amounts of chromium salts and concentrated to afford a white solid, 0.475 g; m.p. 219°-22°; [α]D25° =-41.6° (THF, c=1.5). Tlc on silica (4:1 ethyl acetate:acetic acid) indicated a single spot at Rf =0.79. 'H NMR spectrum (d6 -DMSO) showed triplets at δ9.65 (1H) and δ4.85 (1H, J=7.5 Hz), a singlet at δ7.95 (4H), and a broad multiplet at δ0.9-2.50 (6H) ppm. 13C NMR spectrum (d6 -DMSO) showed single absorptions at 202.9, 170.5, 167.5, 134.9, 131.3, 123.5, 51.7, 42.4, 27.8, and 18.7 ppm.

Workup

  1. additionBy addition
  2. filtrationto 200 ml of ethyl acetate and filtration, chromium salts
  3. customwere removed
  4. concentrationThe filtrate was concentrated under vacuum
  5. dissolutionThe residue was redissolved in 250 ml of ethyl acetate
  6. customto remove trace amounts of chromium salts
  7. concentrationconcentrated
  8. customto afford a white solid, 0.475 g

Sources & evidence

ORD record
ord-8dc2171cdaa0431c80527949fd5a91ea
Source dataset
uspto-grants-1987_04
Patent number
US04661479

Reaction notes

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