Methanol → Benzyloxycarbonyl-asparagine

HRID 647392Notes

Reaction equation

HRID 647392 reaction equation
[NH:1]([C:15]([O:17][CH2:18][C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1)=[O:16])[C@H:2]([C:7](N[C@H](C(O)=O)C)=[O:8])[C@H:3](CC)C.[CH3:25][OH:26].ClC(OCC(C)C)=O.C[N:36]1CCOCC1.[OH2:42]>C(N(CC)CC)C.O1CCCC1.[Pd].CN(C)C=O>[NH:1]([C:15]([O:17][CH2:18][C:19]1[CH:20]=[CH:21][CH:22]=[CH:23][CH:24]=1)=[O:16])[C@H:2]([C:7]([OH:8])=[O:42])[CH2:3][C:25](=[O:26])[NH2:36]

Participants

10

Reactant 5

HCID 887MethanolHCID 962Water2×HCID 79724-MethylmorpholineHCID 62365Isobutyl chloroformateHCID 9217881124787-83-5

Product 1

HCID 75314Benzyloxycarbonyl-asparagine

Reagents, catalysts & solvents 4

HCID 23938PalladiumCatalystHCID 6228DimethylformamideSolventHCID 8028TetrahydrofuranSolvent2×HCID 8471TriethylamineSolvent

Conditions

Temperature
-10 °C

Procedure

3.36 g of Z-Ile-Ala-OH was catalytically reduced in a mixed solvent of 20 ml of methanol and 15 ml of water in the presence of palladium black. The resulting dipeptide was dissolved in 20 ml of water containing 1.4 ml of triethylamine and 16 ml of tetrahydrofuran and cooled to -10° C. To this solution was added a mixed acid anhydride obtained from 3.46 g of Z-Asn-OH, 1.67 ml of isobutyl chloroformate and 1.42 ml of N-methylmorpholine at -10° C. in a mixed solution of 15 ml of dimethylformamide and 20 ml of tetrahydrofuran. The reaction mixture was stirred at 0° C. for 5 minutes, then at 15° C. for 30 minutes followed by distilling off the solvent. To the residue was added 1 N citric acid, and a precipitate thus-formed was washed with water, dried, and reprecipitated from methanol-ethyl acetate to purify. Thus, there was obtained 3.60 g of the end product. m.p. 240°-244° C. (d.); [α]D19 : -13.8° (C: 1.0; dimethylformamide)

Sources & evidence

ORD record
ord-16c063aafa3d4918980201f15141511e
Source dataset
uspto-grants-1983_10
Patent number
US04407965

Reaction notes

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