Ethyl isocyanoacetate → 5-[8-(N-benzyloxycarbonylamino)oct-1-en-2-yl]-oxazoline-4-carboxylic acid ethyl ester

HRID 487456Notes

Reaction equation

HRID 487456 reaction equation
[CH2:1]([O:8][C:9]([NH:11][CH2:12][CH2:13][CH2:14][CH2:15][CH2:16][CH2:17][C:18](=[CH2:21])[CH:19]=[O:20])=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[CH2:22]([O:24][C:25](=[O:29])[CH2:26][N+:27]#[C-:28])[CH3:23]>C1(C)C=CC=CC=1.[Cu-]=O>[CH2:22]([O:24][C:25]([CH:26]1[CH:19]([C:18]([CH2:17][CH2:16][CH2:15][CH2:14][CH2:13][CH2:12][NH:11][C:9]([O:8][CH2:1][C:2]2[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=2)=[O:10])=[CH2:21])[O:20][CH:28]=[N:27]1)=[O:29])[CH3:23]

Participants

5

Reactant 2

HCID 533707Ethyl isocyanoacetateHCID 149666078-(N-benzyloxycarbonylamino)-2-methyleneoctanal

Product 1

HCID 149666085-[8-(N-benzyloxycarbonylamino)oct-1-en-2-yl]-oxazoline-4-carboxylic acid ethyl esterYield 38.3%

Reagents, catalysts & solvents 2

HCID 178419072HCID 178419072, compoundCatalystHCID 1140TolueneSolvent2×

Procedure

15.30 g (52.9 mmol) of 8-(N-benzyloxycarbonylamino)-2-methyleneoctanal and 7.37 ml (67.4 mmol) of isocyanoacetic acid ethyl ester are dissolved in 78 ml of toluene and added dropwise under argon, within a period of 75 minutes, to a suspension of 0.30 g of copper(I) oxide in 76 ml of toluene. The mixture is then stirred for 90 minutes at 30°, cooled to room temperature and filtered, and the clear, bright red filtrate is introduced into a column filled with 250 g of silica gel (particle size 0.04-0.063 mm) and eluted with hexane/ethyl acetate (2:1). Concentration of the suitable fractions by evaporation yields 8.15 g of 5-[8-(N-benzyloxycarbonylamino)oct-1-en-2-yl]-oxazoline-4-carboxylic acid ethyl ester in the form of a colourless honey.

Workup

  1. filtrationfiltered
  2. additionthe clear, bright red filtrate is introduced into a column
  3. additionfilled with 250 g of silica gel (particle size 0.04-0.063 mm)
  4. washeluted with hexane/ethyl acetate (2:1)
  5. customConcentration of the suitable fractions by evaporation

Sources & evidence

ORD record
ord-ac5b08ac5afc4fd893e85b946c5c4f18
Source dataset
uspto-grants-1994_03
Patent number
US05294734

Reaction notes

Loading…