9-Fluorenylmethyl chloroformate → 3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-2,2-dimethylpropanoic acid

HRID 2282850

Reaction equation

HRID 2282850 reaction equation
Cl.[NH2:2][CH2:3][C:4]([CH3:9])([CH3:8])[C:5]([OH:7])=[O:6].C(N(C(C)C)CC)(C)C.[CH:19]1[C:31]2[CH:30]([CH2:32][O:33][C:34](Cl)=[O:35])[C:29]3[C:24](=[CH:25][CH:26]=[CH:27][CH:28]=3)[C:23]=2[CH:22]=[CH:21][CH:20]=1>ClCCl>[CH:19]1[C:31]2[CH:30]([CH2:32][O:33][C:34]([NH:2][CH2:3][C:4]([CH3:9])([CH3:8])[C:5]([OH:7])=[O:6])=[O:35])[C:29]3[C:24](=[CH:25][CH:26]=[CH:27][CH:28]=3)[C:23]=2[CH:22]=[CH:21][CH:20]=1

Participants

5

Reactant 3

HCID 343679-Fluorenylmethyl chloroformateHCID 81531DiisopropylethylamineHCID 534077243-Amino-2,2-dimethylpropanoic acid hydrochloride

Product 1

HCID 450244313-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-2,2-dimethylpropanoic acidYield 45.2%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To 3-amino-2,2-dimethylpropanoic acid, hydrochloride salt (250 mg, 1.63 mmol, 1 eq.) in dichloromethane (4 mL, 0.4 M) was added diisopropylethylamine (859 μL, 4.88 mmol, 3 eq.) followed by (9H-fluoren-9-ylmethoxy)carbonyl chloride (473 mg, 1.79 mmol, 1.1 eq.) The reaction was stirred for 18 hours and then concentrated in vacuo. The residue was taken up in ethyl acetate (3 mL) and washed with 1 M aqueous hydrochloric acid solution (2×1 mL) and with brine. The organic layer was dried over sodium sulfate, filtered, and purified by silica gel chromatography (Gradient: 0% to 100% ethyl acetate in heptane) to give #93 (250 mg, 45%) as an oil. 1H NMR (400 MHz, DMSO-d6) δ 12.22 (s, 1H), 7.89 (d, J=7.4 Hz, 2H), 7.72 (d, J=7.4 Hz, 2H), 7.38-7.44 (m, 2H), 7.27-7.35 (m, 3H), 4.18-4.30 (m, 3H), 3.16 (d, J=6.2 Hz, 2H), 1.05 (s, 6H).

Workup

  1. concentrationconcentrated in vacuo
  2. washwashed with 1 M aqueous hydrochloric acid solution (2×1 mL) and with brine
  3. dry with materialThe organic layer was dried over sodium sulfate
  4. filtrationfiltered
  5. custompurified by silica gel chromatography (Gradient: 0% to 100% ethyl acetate in heptane)

Sources & evidence

ORD record
ord-a93fe4d356de4c97912db70422dbd9bf
Source dataset
uspto-grants-2015_09
Patent number
US09138486B2

Linked notes

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