Dicyclohexylcarbodiimide → N-BOC-6-aminocaproic acid, N'-FMOC hydrazide

HRID 1728394Notes

Reaction equation

HRID 1728394 reaction equation
[C:1]([NH:8][CH2:9][CH2:10][CH2:11][CH2:12][CH2:13][C:14]([OH:16])=O)([O:3][C:4]([CH3:7])([CH3:6])[CH3:5])=[O:2].[C:17]([O:21][CH2:22][CH:23]1[C:35]2[CH:34]=[CH:33][CH:32]=[CH:31][C:30]=2[C:29]2[C:24]1=[CH:25][CH:26]=[CH:27][CH:28]=2)(=[O:20])[NH:18][NH2:19].C1(N=C=NC2CCCCC2)CCCCC1>CN(C)C=O>[C:17]([NH:18][NH:19][C:14](=[O:16])[CH2:13][CH2:12][CH2:11][CH2:10][CH2:9][NH:8][C:1]([O:3][C:4]([CH3:5])([CH3:6])[CH3:7])=[O:2])([O:21][CH2:22][CH:23]1[C:35]2[C:30](=[CH:31][CH:32]=[CH:33][CH:34]=2)[C:29]2[C:24]1=[CH:25][CH:26]=[CH:27][CH:28]=2)=[O:20]

Participants

5

Reactant 3

HCID 10868DicyclohexylcarbodiimideHCID 1618839-Fluorenylmethyl carbazateHCID 6376026-((tert-Butoxycarbonyl)amino)hexanoic acid

Product 1

HCID 58794968N-BOC-6-aminocaproic acid, N'-FMOC hydrazideYield 60.8%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
0 °C

Procedure

A 250 ml round bottom flask was charged with 4,190 g (0.0181 mol) of N-BOC-6-aminocaproic acid, 4.60 g of 9-fluorenylmethyl carbazate (FMOC), (prepared by the method of Carpino et. al., 1972, J. Org. Chem., 37:3404) and 35 ml of N,N-dimethylformamide. The reaction solution was cooled to 0° C. and then 3.75 g (0.0182 mol) of 1,3-dicyclohexylcarbodiimide (Aldrich) was added. The reaction mixture was allowed to stir for 2 h at 0° C. The white precipitate which formed during this time was filtered off and the solvents evaporated under reduced pressure. The distillation residue was applied to a 225 cc pad of silica gel (Merck), which was then washed with 1L of chloroform. The product was then eluted from the column using 1L of 50% methanol in chloroform. The solvents were evaporated from the desired eluent fractions to give 4.98 g (0.011 mol, 59% yield) of N-BOC-6-aminocaproic acid (N'-FMOC-hydrazide) as a yellow oil. 1H NMR (DMSO-d6) showed the peaks observed in the starting material and new protons in the aromatic region between 7-8 ppm (FMOC group).

Workup

  1. custom(prepared by the method of Carpino et. al., 1972, J
  2. customThe white precipitate which formed during this time
  3. filtrationwas filtered off
  4. customthe solvents evaporated under reduced pressure
  5. washwas then washed with 1L of chloroform
  6. washThe product was then eluted from the column
  7. customThe solvents were evaporated from the desired eluent fractions

Sources & evidence

ORD record
ord-ebc9cd5aa9f349a6b30baba330497a15
Source dataset
uspto-grants-1994_07
Patent number
US05326856

Reaction notes

Loading…