1-tert-Butyl 2-methyl (2R)-4-oxopyrrolidine-1,2-dicarboxylate Chemical Properties

Boiling point:

333.1±42.0 °C(Predicted)

Density 

1.209

storage temp. 

under inert gas (nitrogen or Argon) at 2-8°C

pka

-3.86±0.40(Predicted)

Appearance

Off-white to yellow Solid-Liquid Mixture

InChI

InChI=1S/C11H17NO5/c1-11(2,3)17-10(15)12-6-7(13)5-8(12)9(14)16-4/h8H,5-6H2,1-4H3/t8-/m1/s1

InChIKey

UPBHYYJZVWZCOZ-MRVPVSSYSA-N

SMILES

N1(C(OC(C)(C)C)=O)CC(=O)C[C@@H]1C(OC)=O

Safety Information

HazardClass 

IRRITANT

HS Code 

2933998090

1-tert-Butyl 2-methyl (2R)-4-oxopyrrolidine-1,2-dicarboxylate Usage And Synthesis

Uses

N-Boc-4-oxo-D-Proline methyl ester is a useful chemical reagent.

Synthesis

General procedure for the synthesis of (R)-1-tert-butyl 2-methyl 4-oxopyrrolidine-1,2-dicarboxylates from methyl (2R,4R)-1-Boc-4-hydroxypyrrolidine-2-carboxylate: Step 1: Oxidation reaction Pyridinium dichromate (9.97 g, 26.5 mmol) was dissolved in dichloromethane (60 mL) at room temperature and slowly added to a dichloromethane solution of methyl (2R,4R)-1-Boc-4-hydroxypyrrolidine-2-carboxylate (5.00 g, 20.39 mmol). The reaction mixture was stirred at room temperature overnight. After completion of the reaction, diatomaceous earth (5 g) was added and stirring was continued for 40 min, followed by filtration. The filter cake was washed with dichloromethane (50 mL x 3). The filtrates were combined, concentrated to dryness under reduced pressure, added toluene (40 mL) and concentrated again to give about 6.5 g of brown slurry-like crude product. Purification step The crude product was purified by fast silica gel column chromatography (120 g silica gel column, eluent EtOAc/hexane, gradient 0 to 100%, flow rate 85 mL/min) to afford 4.18 g (84% yield) of (R)-1-tert-butyl 2-methyl 4-oxopyrrolidine-1,2-dicarboxylate as a white solid. Product characterization LCMS (condition A): m/z 144 (M-Boc)-ve. 1H NMR (400 MHz, CDCl3) δ ppm: 4.44-4.89 (1H, m), 3.84-3.96 (2H, m), 3.77 (3H, s), 2.81-3.10 (1H, m), 2.59 (1H, dd, J = 18.93, 1.76 Hz), 1.52 (9H, s).

References

[1] Patent: WO2012/125887, 2012, A1. Location in patent: Page/Page column 74-75
[2] Patent: WO2012/125886, 2012, A1. Location in patent: Page/Page column 85
[3] Patent: WO2015/94902, 2015, A1. Location in patent: Page/Page column 20; 21
[4] Journal of Medicinal Chemistry, 1999, vol. 42, # 26, p. 5426 - 5436
[5] Patent: TW2017/8221, 2017, A. Location in patent: Page/Page column 41; 42

1-tert-Butyl 2-methyl (2R)-4-oxopyrrolidine-1,2-dicarboxylate(256487-77-1)Related Product Information

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