24666-56-6

Basic information

• Product Name: 2,6-Dioxopiperidine-3-ammonium chloride
• Synonyms: 2,6-Dioxopiperidine-3-ammonium chloride;3-amino piperdine-2,6-dion hydrochloride;3-Amino-2,6-piperidinedione hydrochloride;2,6-Piperidinedione, 3-amino-, hydrochloride;Glutamic acid imide hydrochloride;3-Amino-2,6-dioxo-piperidine hydrochloride ,99%;3-AMino-2,6-Piperidinedione HCl;3-AMino-2,6-dioxo-piperidine hydrochloride
• CAS NO: 24666-56-6
• Molecular Formula: C₅H₈N₂O₂*ClH
• Molecular Weight: 164.59016
• EINECS: 2017-001-1
• Product Categories: Pyrrolidines
• Mol File: 24666-56-6.mol
• Article Data: 8

Chemical Properties

• Melting Point: 120 °C (approx)
• Boiling Point: 334.5 °C at 760 mmHg
• Flash Point: 156.1 °C
• Appearance: /
• Vapor Pressure: 0.000128mmHg at 25°C
• Storage Temp.: Inert atmosphere,Room Temperature
• CAS DataBase Reference: 2,6-Dioxopiperidine-3-ammonium chloride(CAS DataBase Reference)
• NIST Chemistry Reference: 2,6-Dioxopiperidine-3-ammonium chloride(24666-56-6)
• EPA Substance Registry System: 2,6-Dioxopiperidine-3-ammonium chloride(24666-56-6)

Safety Data

• Statements: 20/21/22
• Safety Statements: 3/9-36/37
• Hazardous Substances Data: 24666-56-6(Hazardous Substances Data)

Usage

Description

2,6-Dioxopiperidine-3-ammonium chloride is a reagent for preparing lenalidomide that can induce ubiquitination and degradation of CK1α in del (5q) MDS. It can also be used to prepare phthalimide conjugates that can promote ligand-dependent target protein degradation. Moreover, it is also a metabolite of thalidomide (T338850) that inhibits FGF-induced angiogenesis.

Chemical Properties

White crystal

InChI:InChI=1/C5H8N2O2.ClH/c6-3-1-2-4(8)7-5(3)9;/h3H,1-2,6H2,(H,7,8,9);1H

Synthetic route

3-(benzyloxycarbonyl)-amino-2,6-dioxopiperidine (24666-55-5) → rac-α-aminoglutarimide hydrochloride (24666-56-6)

Conditions	Yield
With hydrogenchloride; hydrogen; 5% palladium over charcoal In methanol; water under 3102.97 Torr; for 4h;	100%
With hydrogenchloride In dimethyl sulfoxide	92%
Stage #1: 3-(benzyloxycarbonyl)-amino-2,6-dioxopiperidine With palladium 10% on activated carbon; hydrogen In methanol; water at 25 - 30℃; under 2250.23 - 2625.26 Torr; Stage #2: With hydrogenchloride In methanol; water at 25 - 30℃;	90%
With hydrogenchloride; palladium 10% on activated carbon; hydrogen In methanol at 25℃; for 5h;	90.5%
With hydrogenchloride; hydrogen; palladium on activated charcoal In ethyl acetate under 2585.74 - 3102.89 Torr;

(RS)-(2,6-dioxopiperidin-3-yl)carbamic acid tert-butyl ester (31140-42-8) → rac-α-aminoglutarimide hydrochloride (24666-56-6)

Conditions	Yield
With hydrogenchloride In methanol; water for 2h;	99%

N-(2,6-dioxopiperidin-3-yl)-2-phenylacetamide → rac-α-aminoglutarimide hydrochloride (24666-56-6)

Conditions	Yield
With hydrogenchloride; hydrogen; palladium 10% on activated carbon In methanol under 760.051 Torr; for 23h;	96%

Glutamic acid (617-65-2) → rac-α-aminoglutarimide hydrochloride (24666-56-6)

Conditions	Yield
Stage #1: Glutamic acid With ammonium hydroxide In water at 15℃; for 0.5h; Stage #2: In water at 60℃; for 2h; Stage #3: With hydrogenchloride In ethanol at 30℃; Temperature;	82.6%

<(S)-2,6-dioxo-<3>piperidyl>-carbamic acid benzyl ester → rac-α-aminoglutarimide hydrochloride (24666-56-6)

Conditions	Yield
With hydrogenchloride; palladium Hydration;

Cbz-L-Gln (2650-64-8) → rac-α-aminoglutarimide hydrochloride (24666-56-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: CDI / tetrahydrofuran / Heating 2: H2, aq. HCl / 10 percent Pd/C / ethyl acetate / 2585.74 - 3102.89 Torr View Scheme
Multi-step reaction with 2 steps 1: dmap; 1,1'-carbonyldiimidazole / 1,4-dioxane / 15 h / 100 °C 2: palladium 10% on activated carbon; hydrogen; hydrogenchloride / methanol / 5 h / 25 °C View Scheme

N-benzyloxycarbonyl-L-isoglutamine (6398-06-7) → rac-α-aminoglutarimide hydrochloride (24666-56-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: dmap; 1,1'-carbonyldiimidazole / tetrahydrofuran / 20 h / Reflux 2: hydrogenchloride; hydrogen / palladium 10% on activated carbon / methanol / 23 h / 760.05 Torr View Scheme

L-glutamic acid (56-86-0) → rac-α-aminoglutarimide hydrochloride (24666-56-6)

Conditions	Yield
Multi-step reaction with 3 steps 1: water / 2 h / 0 °C 2: urea / dimethyl sulfoxide / 2 h / 150 °C 3: hydrogenchloride / dimethyl sulfoxide View Scheme

N-benzyloxycarbonyl-L-glutamic acid (1155-62-0) → rac-α-aminoglutarimide hydrochloride (24666-56-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: urea / dimethyl sulfoxide / 2 h / 150 °C 2: hydrogenchloride / dimethyl sulfoxide View Scheme

Nα-benzyloxycarbonyl-glutamine (50516-14-8) → rac-α-aminoglutarimide hydrochloride (24666-56-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: dmap; 1,1'-carbonyldiimidazole / 1,4-dioxane / 17.17 h / 20 °C / Heating / reflux 2: hydrogenchloride; hydrogen / 5% palladium over charcoal / methanol; water / 4 h / 3102.97 Torr View Scheme

rac-α-aminoglutarimide hydrochloride (24666-56-6) + 2-bromomethyl-3-nitro-benzoic acid methyl ester (98475-07-1) → 3-(4-nitro-1-oxoisoindolin-2-yl)piperidine-2,6-dione (827026-45-9)

Conditions	Yield
Stage #1: rac-α-aminoglutarimide hydrochloride With triethylamine In dimethyl sulfoxide for 0.166667h; Inert atmosphere; Stage #2: 2-bromomethyl-3-nitro-benzoic acid methyl ester In dimethyl sulfoxide at 50 - 55℃; for 12.3333h; Inert atmosphere;	99.73%
With sodium carbonate at 100℃; for 0.75h; Reagent/catalyst; Temperature; Inert atmosphere;	98.5%
With sodium carbonate In acetonitrile at 70℃; for 8h; Solvent; Reagent/catalyst; Temperature;	98.8%

3-bromophthalic anhydride (82-73-5) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 4-bromo-2-(2,6-dioxopiperidin-3-yl)isoindoline-1,3-dione

Conditions	Yield
With potassium acetate; acetic acid at 90℃; for 16h;	99%
With potassium acetate; acetic acid at 90℃; for 16h; Inert atmosphere;	99%
With sodium acetate; acetic acid for 3h; Reflux;	94.1%

4-[4,4-difluoro-5-[4-[3-[[5-(5-methylpyrido[4,3-b]indol-7-yl)-2-pyridyl]oxy]cyclobutoxy]-1-piperidyl]pentoxy]phthalic acid + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 5-[4,4-difluoro-5-[4-[3-[[5-(5-methylpyrido[4,3-b]indol-7-yl)-2-pyridyl]oxy]cyclobutoxy]-1-piperidyl]pentoxy]-2-(2,6-dioxo-3-piperidyl)isoindolin-1,3-dione

Conditions	Yield
Stage #1: 4-[4,4-difluoro-5-[4-[3-[[5-(5-methylpyrido[4,3-b]indol-7-yl)-2-pyridyl]oxy]cyclobutoxy]-1-piperidyl]pentoxy]phthalic acid With sodium acetate; acetic acid at 25℃; for 1h; Stage #2: rac-α-aminoglutarimide hydrochloride at 120℃; for 11h;	98%

3-acetylaminophthalic acid (15371-06-9) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → N-(2-(2,6-dioxopiperidin-3-yl)-1,3-dioxoisoindolin-4-yl)acetamide (444289-17-2)

Conditions	Yield
With potassium acetate In 1,4-dioxane at 100℃; for 24h; Reagent/catalyst; Solvent; Temperature;	97.5%

3-hydroxyphthalic anhydride (37418-88-5) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 4-Hydroxythalidomide (5054-59-1)

Conditions	Yield
With potassium acetate In acetic acid for 24h; Reflux;	96%
With sodium acetate; acetic acid at 100℃; for 2h;	96%
With pyridine at 110℃;	93%

4-fluorophthalic anhydride (319-03-9) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 2-(2,6-dioxopiperidin-3-yl)-5-fluoro-2,3-dihydro-1H-isoindole-1,3-dione (835616-61-0)

Conditions	Yield
With sodium acetate; acetic acid at 120℃; for 12h;	96%
With sodium acetate; acetic acid at 135℃;	92%
With sodium acetate In acetic acid for 12h; Reflux;	90%

benzyl (4-(2-((1,3-dioxo-1,3-dihydroisobenzofuran-4-yl)oxy)acetamido)butyl)carbamate + rac-α-aminoglutarimide hydrochloride (24666-56-6) → benzyl (4-(2-((2-(2,6-dioxopiperidin-3-yl)-1,3-dioxoisoindolin-4-yl)oxy)acetamido)butyl)carbamate

Conditions	Yield
Stage #1: benzyl (4-(2-((1,3-dioxo-1,3-dihydroisobenzofuran-4-yl)oxy)acetamido)butyl)carbamate; rac-α-aminoglutarimide hydrochloride With triethylamine In tetrahydrofuran for 3h; Reflux; Inert atmosphere; Stage #2: With 1,1'-carbonyldiimidazole In tetrahydrofuran Reflux; Inert atmosphere;	96%

phthalic anhydride (85-44-9) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → thalidomide (50-35-1)

Conditions	Yield
With acetic acid; triethylamine for 3h; Temperature; Reagent/catalyst; Concentration; Reflux;	95%

3-acetylaminophthalic anhydride (6296-53-3) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → N-(2-(2,6-dioxopiperidin-3-yl)-1,3-dioxoisoindolin-4-yl)acetamide (444289-17-2)

Conditions	Yield
With sodium acetate; acetic acid at 105℃; for 24h; Reagent/catalyst; Temperature;	95%

3-hydroxy-1,8-naphthalic acid anhydride (23204-36-6) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 2-(2,6-dioxopiperidin-3-yl)-5-hydroxy-1H-benzo[de]isoquinoline-1,3(2H)-dione

Conditions	Yield
With triethylamine In tetrahydrofuran for 120h; Reflux;	95%
With triethylamine In tetrahydrofuran for 120h; Reflux;	3.44 g

rac-α-aminoglutarimide hydrochloride (24666-56-6) + 3-aminophthalic acid hydrochloride (6946-22-1) → pomalidomide (19171-19-8)

Conditions	Yield
Stage #1: rac-α-aminoglutarimide hydrochloride; 3-aminophthalic acid hydrochloride In acetonitrile for 0.25h; Stage #2: With triethylamine In water; acetonitrile at 15 - 87℃; for 49.0833 - 50.8333h; Product distribution / selectivity;	94%
Stage #1: rac-α-aminoglutarimide hydrochloride; 3-aminophthalic acid hydrochloride In acetonitrile for 0.25h; Stage #2: With 1H-imidazole In water; acetonitrile at 15 - 87℃; for 7.08333 - 10.8333h; Product distribution / selectivity;	92%
Stage #1: rac-α-aminoglutarimide hydrochloride; 3-aminophthalic acid hydrochloride With acetic acid In acetonitrile for 0.25h; Stage #2: With 1H-imidazole In water; acetonitrile at 15 - 87℃; for 7.08333 - 10.8333h; Product distribution / selectivity;	85%
Stage #1: rac-α-aminoglutarimide hydrochloride; 3-aminophthalic acid hydrochloride With acetic acid In acetonitrile for 0.25h; Stage #2: With triethylamine In water; acetonitrile at 15 - 87℃; for 7.08333 - 10.8333h; Product distribution / selectivity;	84%
With acetic acid; triethylamine In acetone at 80 - 85℃; for 6h;	68.5%

4,5-difluorophthalic anhydride (18959-30-3) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 2-(2,6-dioxopiperidin-3-yl)-5,6-difluoroisoindoline-1,3-dione

Conditions	Yield
With potassium acetate; acetic acid at 90℃;	94%
With potassium acetate; acetic acid at 110℃;
With triethylamine In toluene at 100℃; for 4h;

methyl 2-(chloromethyl)-3-nitrobenzoate + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 3-(4-nitro-1-oxoisoindolin-2-yl)piperidine-2,6-dione (827026-45-9)

Conditions	Yield
With triethylamine In acetonitrile at 80℃; for 10h;	93.2%

4-bromophthalic anhydride (86-90-8) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 5-bromo-2-(2,6-dioxopiperidin-3-yl)-2,3-dihydro-1H-isoindole-1,3-dione (26166-92-7)

Conditions	Yield
With sodium acetate; acetic acid Heating / reflux;	93%
With sodium acetate In acetic acid at 20 - 80℃; for 16h;	92%
With sodium acetate; acetic acid at 115℃; for 16h;	91.6%
With potassium acetate; acetic acid at 90℃; for 12h;	60%
With sodium acetate; acetic acid at 120℃; for 5h;

C20H15NO5 (927672-71-7) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 4-(2-phenoxyphenylamino)-2-(2,6-dioxopiperidin-3-yl)isoindole-1,3-dione (927671-10-1)

Conditions	Yield
With pyridine for 16h; Heating / reflux;	93%

3-(4-tert-butylphenylamino)phthalic acid (927672-50-2) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 4-(4-tert-butylphenylamino)-2-(2,6-dioxopiperidin-3-yl)isoindole-1,3-dione (927670-99-3)

Conditions	Yield
With pyridine for 16h; Heating / reflux;	92%

3-(naphthalen-2-ylamino)phthalic acid (927672-63-7) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 2-(2,6-Dioxopiperidin-3-yl)-4-(naphthalen-2-ylamino)isoindole-1,3-dione (927671-06-5)

Conditions	Yield
With pyridine for 16h; Heating / reflux;	92%

3-(2-methoxyphenylamino)phthalic acid (927672-67-1) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 4-(2-Methoxyphenylamino)-2-(2,6-dioxopiperidin-3-yl)isoindole-1,3-dione (927671-08-7)

Conditions	Yield
With pyridine for 16h; Heating / reflux;	92%

3-fluorophthalic anhydride (652-39-1) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 2‐(2,6‐dioxopiperidin‐3‐yl)‐4‐fluoroisoindoline‐1,3‐dione

Conditions	Yield
With sodium acetate; acetic acid at 135℃;	92%
With sodium acetate; acetic acid for 12h; Reflux;	90%
With sodium acetate In acetic acid for 12h; Reflux;	90%

Indole-2-carboxylic acid (1477-50-5) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → N-(2,6-dioxopiperidin-3-yl)-1H-indole-2-carboxamide

Conditions	Yield
Stage #1: Indole-2-carboxylic acid With N-ethyl-N,N-diisopropylamine; N-[(dimethylamino)-3-oxo-1H-1,2,3-triazolo[4,5-b]pyridin-1-yl-methylene]-N-methylmethanaminium hexafluorophosphate In N,N-dimethyl-formamide at 20℃; for 1h; Inert atmosphere; Stage #2: rac-α-aminoglutarimide hydrochloride In N,N-dimethyl-formamide at 20℃; Inert atmosphere;	92%

rac-α-aminoglutarimide hydrochloride (24666-56-6) + 2-chloropyridine-3,4-dicarboxylic acid → 4-chloro-2-(2,6-dioxopiperidin-3-yl)-1H-pyrrolo[3,4-c]pyridine-1,3(2H)-dione

Conditions	Yield
With 1,1'-carbonyldiimidazole In acetonitrile for 16h;	91.7%
With 1,1'-carbonyldiimidazole In acetonitrile at 80℃; for 16h; Inert atmosphere;	27%

3-nitrophthalic acid anhydride (641-70-3) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 2-((2,6-dioxopiperidin-3-yl)carbamoyl)-3-nitrobenzoic acid

Conditions	Yield
With triethylamine In tetrahydrofuran at 20℃; for 0.5h; Reagent/catalyst; Green chemistry;	91%
With triethylamine In tetrahydrofuran at 20℃; for 0.5h;	91%
With triethylamine In tetrahydrofuran at 20℃; for 0.5h;	91%

3-nitrophthalic acid (603-11-2) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 4-NT (19171-18-7)

Conditions	Yield
With sodium acetate; acetic acid at 105 - 115℃; Large scale;	90%
With sodium acetate; acetic acid In water at 116 - 118℃; for 16h;	86.2%
With 1,1'-carbonyldiimidazole In acetonitrile at 20 - 80℃; Inert atmosphere;	28.2 g

rac-α-aminoglutarimide hydrochloride (24666-56-6) + 2-Nitrobenzenesulfonyl chloride (1694-92-4) → N-(2,6-dioxopiperidin-3-yl)-2-nitrobenzenesulfonamide

Conditions	Yield
Stage #1: rac-α-aminoglutarimide hydrochloride With N-ethyl-N,N-diisopropylamine In N,N-dimethyl-formamide at 20℃; for 0.5h; Stage #2: 2-Nitrobenzenesulfonyl chloride In N,N-dimethyl-formamide at 0 - 20℃;	90%

2-Iodobenzoic acid (88-67-5) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → N-(2,6-dioxopiperidin-3-yl)-2-iodobenzamide

Conditions	Yield
Stage #1: 2-Iodobenzoic acid With N-ethyl-N,N-diisopropylamine; N-[(dimethylamino)-3-oxo-1H-1,2,3-triazolo[4,5-b]pyridin-1-yl-methylene]-N-methylmethanaminium hexafluorophosphate In N,N-dimethyl-formamide for 0.166667h; Stage #2: rac-α-aminoglutarimide hydrochloride In N,N-dimethyl-formamide at 20℃; for 2h;	90%
Stage #1: 2-Iodobenzoic acid With N-ethyl-N,N-diisopropylamine; N-[(dimethylamino)-3-oxo-1H-1,2,3-triazolo[4,5-b]pyridin-1-yl-methylene]-N-methylmethanaminium hexafluorophosphate In N,N-dimethyl-formamide at 20℃; for 1h; Inert atmosphere; Stage #2: rac-α-aminoglutarimide hydrochloride In N,N-dimethyl-formamide at 20℃; Inert atmosphere;	73%

3-nitrophthalic acid anhydride (641-70-3) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 4-NT (19171-18-7)

Conditions	Yield
With sodium acetate; acetic acid at 25 - 118℃; for 18h;	89.7%
With formic acid; ammonium formate at 80℃; for 0.166667h; Temperature;	89%
With sodium acetate; acetic acid In water at 116 - 118℃; for 17h;	88.3%

3-(4-isopropylphenylamino)phthalic acid (927672-52-4) + rac-α-aminoglutarimide hydrochloride (24666-56-6) → 4-(4-isopropylphenylamino)-2-(2,6-dioxopiperidin-3-yl)isoindole-1,3-dione (927671-00-9)

Conditions	Yield
With pyridine for 16h; Heating / reflux;	89%

Upstream product

• 24666-55-5 3-(benzyloxycarbonyl)-amino-2,6-dioxopiperidine 
• 31140-42-8 (RS)-(2,6-dioxopiperidin-3-yl)carbamic acid tert-butyl ester 
• 617-65-2 Glutamic acid 
• 50516-14-8 Nα-benzyloxycarbonyl-glutamine 
• 1155-62-0 N-benzyloxycarbonyl-L-glutamic acid 
• 56-86-0 L-glutamic acid 
• 77658-84-5 N-(2,6-dioxopiperidin-3-yl)-2-phenylacetamide 
• 6398-06-7 N-benzyloxycarbonyl-L-isoglutamine 
• 2650-64-8 Cbz-L-Gln 

Downstream Products

• 827026-45-9 3-(4-nitro-1-oxoisoindolin-2-yl)piperidine-2,6-dione 
• 19171-19-8 pomalidomide 
• 1015474-80-2 2-amino-N-(2,6-dioxopiperidin-3-yl)-6-methylbenzamide 
• 1015474-85-7 2-amino-6-chloro-N-(2,6-dioxopiperidin-3-yl)benzamide 
• 1243329-97-6 (RS)-3-(4-amino-1-oxo-1,3-dihydroisoindol-2-yl)piperidine-2,6-dione hydrochloride 
• 879126-98-4 Lenalidomide 

Relevant articles and documents

Traceless Staudinger ligation enabled parallel synthesis of proteolysis targeting chimera linker variants

A parallel, one-pot assembly approach to proteolysis targeting chimeras (PROTACs) is demonstrated utilizing activated esters generatedin situ, and traceless Staudinger ligation chemistry. The method described allows for rapid structure-activity relationship studies of PROTAC linker variants. Two previously studied systems, cereblon and BRD4 degraders, are examined as test cases for the synthetic method. The two related strategies to assemble PROTAC linker variants discussed can accommodate the chromotographic separations capabilities of labs of many sizes and incorporates commercially available degrader building blocks, thereby easing synthetic entry into PROTAC chemical space.

Preparation method of lenadomide

The invention discloses a preparation method of lenalidomide, and belongs to the field of organic synthesis. 2-methyl-3-methyl nitrobenzoate and 3-N-benzyloxy-carbonyl-L-glutamine serve as starting materials, and an important intermediate 2-brooethyl-3-methyl nitrobenzoate is obtained through a bromination reaction of 2-methyl-3-methyl nitrobenzoate. 3-N-benzyloxy-carbonyl-L-glutamine is cyclizedunder catalysis to produce 3-N-benzyloxy-carbonyl-2,6-dioxopiperidine, an amino group is subjected to deprotection to produce 3-amino-2,6-piperidone halide, 3-(4-nitro-1-oxo-1,3-o-xylylenimine-2-yl)piperidine-2,6-diketone is obtained through an aminolysis reaction of 3-N-benzyloxy-carbonyl-2,6-dioxopiperidine and 2-brooethyl-3-methyl nitrobenzoate, and then lenalidomide is prepared through reduction. The method has the advantages that the cost of raw materials are low, aftertreatment is simple, and the yield is high, and the production cost of the lenalidomide as a bulk drug is greatly reduced. The method is a convenient and efficient lenalidomide synthesis method suitable for industrial production.

PROCESS FOR THE PREPARATION OF POMALIDOMIDE

The present invention relates to a process for the preparation of pomalidomide. The present invention also provides a process for the preparation of 2-(2,6-dioxopiperidin-3-yl)-4-nitro-1H-isoindole-1,3(2H)-dione, a compound of Formula II and its use for the preparation of pomalidomide. The pomalidomide may be made having a yield greater than 97% and the 2-(2,6-dioxopiperidin-3-yl)-4-nitro-1H-isoindole-1,3(2H)-dione (Formula II) may be made having a yield greater than 88%.