2748-02-9

Basic information

• Product Name: L-Leucine tert-butyl ester hydrochloride
• Synonyms: l-leucinet-butylesterhydrochloride*crystalline;LEUCINE-OTBU HCL;L-LEUCINE, 1,1-DIMETHYLETHYL ESTER, HYDROCHLORIDE;L-LEUCINE TERT-BUTYL ESTER HYDROCHLORIDE;L-LEUCINE T-BUTYL ESTER;L-LEUCINE T-BUTYL ESTER HCL;L-LEUCINE T-BUTYL ESTER HCL SALT;L-LEUCINE T-BUTYL ESTER HYDROCHLORIDE
• CAS NO: 2748-02-9
• Molecular Formula: C₁₀H₂₁NO₂*ClH
• Molecular Weight: 223.74
• Product Categories: Amino Acid Derivatives;Leucine [Leu, L];Amino Acids and Derivatives;Amino hydrochloride;Amino Acids;I - Z;Modified Amino Acids
• Mol File: 2748-02-9.mol
• Article Data: 0

Chemical Properties

• Melting Point: 167°C(lit.)
• Boiling Point: 222.4 °C at 760 mmHg
• Flash Point: 90.3 °C
• Appearance: White/Crystalline Powder
• Density: 0.929g/cm3
• Vapor Pressure: 0.102mmHg at 25°C
• Refractive Index: 1.444
• Storage Temp.: 2-8°C
• CAS DataBase Reference: L-Leucine tert-butyl ester hydrochloride(CAS DataBase Reference)
• NIST Chemistry Reference: L-Leucine tert-butyl ester hydrochloride(2748-02-9)
• EPA Substance Registry System: L-Leucine tert-butyl ester hydrochloride(2748-02-9)

Safety Data

• Safety Statements: 24/25
• WGK Germany: 3
• HazardClass: IRRITANT
• Hazardous Substances Data: 2748-02-9(Hazardous Substances Data)

Usage

Description

L-Leucine tert-butyl ester hydrochloride is a chemical compound derived from L-Leucine, an essential amino acid. It is a protected form of L-Leucine, which means it has been modified to enhance its stability and reactivity in various chemical reactions. L-Leucine tert-butyl ester hydrochloride is characterized by its crystalline structure and is known for its specific biological activities and potential applications in different industries.

Uses

Used in Pharmaceutical Industry:
L-Leucine tert-butyl ester hydrochloride is used as a building block for the synthesis of various pharmaceutical compounds. Its role as a protected form of L-Leucine allows for the development of new drugs with improved properties and therapeutic effects.
Used in Research and Development:
In the field of research and development, L-Leucine tert-butyl ester hydrochloride serves as an important compound for studying the effects of L-Leucine on blood glucose levels and its potential as a tumor promoter. This knowledge can be applied to develop new treatments for idiopathic familial hypoglycemia and bladder cancer.
Used in Nutritional Supplements:
L-Leucine tert-butyl ester hydrochloride can be used as an ingredient in nutritional supplements, particularly for individuals with idiopathic familial hypoglycemia. Its ability to induce a sharp decrease in blood glucose levels may provide a potential therapeutic benefit for these patients.
Used in Chemical Synthesis:
Due to its unique chemical properties, L-Leucine tert-butyl ester hydrochloride can be employed as an intermediate in the synthesis of various chemical compounds. Its crystalline structure and reactivity make it a valuable component in the development of new materials and products.

InChI:InChI=1/C10H21NO2/c1-7(2)6-8(11)9(12)13-10(3,4)5/h7-8H,6,11H2,1-5H3/t8-/m0/s1

Synthetic route

N-Cbz-L-Isoleucine (3160-59-6) + L-leucine tert-butyl ester hydrochloride (2748-02-9) → N-benzyloxycarbonyl-L-isoleucyl-L-leucine t-butyl ester (69531-03-9)

Conditions	Yield
With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine In dichloromethane; water; N,N-dimethyl-formamide at 20℃;	100%
With 4-methyl-morpholine; (benzotriazo-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate In N,N-dimethyl-formamide for 2h;	88%

4-(1-ethyl-propylamino)-3-nitro-benzoic acid (691363-43-6) + L-leucine tert-butyl ester hydrochloride (2748-02-9) → (S)-2-[4-(1-ethyl-propylamino)-3-nitro-benzoylamino]-4-methyl-pentanoic acid tert-butyl ester (1586791-35-6)

Conditions	Yield
With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; N-ethyl-N,N-diisopropylamine In N,N-dimethyl-formamide at 20℃; for 4h;	100%

3-nitro-4-fluorobenzoic acid (453-71-4) + L-leucine tert-butyl ester hydrochloride (2748-02-9) → (S)-2-(4-fluoro-3-nitro-benzoylamino)-4-methyl-pentanoic acid tert-butyl ester (1586791-32-3)

Conditions	Yield
Stage #1: 3-nitro-4-fluorobenzoic acid With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; N-ethyl-N,N-diisopropylamine In N,N-dimethyl-formamide at 0℃; for 0.5h; Stage #2: L-leucine tert-butyl ester hydrochloride With N-ethyl-N,N-diisopropylamine In N,N-dimethyl-formamide for 4h;	100%
With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; N-ethyl-N,N-diisopropylamine In N,N-dimethyl-formamide at 0 - 20℃; for 4h;

L-leucine tert-butyl ester hydrochloride (2748-02-9) + Nα-(9-fluorenylmethyloxycarbonyl)-Nγ-2,2,4,6,7-pentamethyldihydrobenzofuran-5-sulfonyl-L-arginine → Fmoc-Arg(Pbf)-Leu-Ot-Bu

Conditions	Yield
Stage #1: L-leucine tert-butyl ester hydrochloride; Nα-(9-fluorenylmethyloxycarbonyl)-Nγ-2,2,4,6,7-pentamethyldihydrobenzofuran-5-sulfonyl-L-arginine With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride In tetrahydrofuran for 0.5h; Cooling with ice; Stage #2: With 4-methyl-morpholine In tetrahydrofuran for 4h; Cooling with ice;	100%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + (2R,3R)-N-(tert-butoxycarbonyl)-3-amino-2-hydroxy-4-phenylbutanoic acid (77171-41-6) → N-[(2R,3R)-3-(tert-butoxycarbonyl)amino-2-hydroxy-4-phenylbutanoyl]-L-leucine tert-butyl ester (1242168-90-6)

Conditions	Yield
Stage #1: L-leucine tert-butyl ester hydrochloride; (2R,3R)-N-(tert-butoxycarbonyl)-3-amino-2-hydroxy-4-phenylbutanoic acid In tetrahydrofuran for 0.5h; Cooling with ice; Stage #2: With benzotriazol-1-ol; triethylamine; dicyclohexyl-carbodiimide In tetrahydrofuran at 0℃; Concentration;	99.3%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + cycloheptan-3-on-1-yl 2,3,4,6-tetra-O-lauroyl-1-thio-β-D-galactopyranoside (215312-93-9) → Dodecanoic acid (2S,3R,4S,5S,6R)-2-[3-((S)-1-tert-butoxycarbonyl-3-methyl-butylamino)-cycloheptylsulfanyl]-4,5-bis-dodecanoyloxy-6-dodecanoyloxymethyl-tetrahydro-pyran-3-yl ester (215313-23-8)

Conditions	Yield
With sodium cyanoborohydride In tetrahydrofuran; acetonitrile for 73h;	99%

Fmoc-Pro-OH (71989-31-6) + L-leucine tert-butyl ester hydrochloride (2748-02-9) → (9H-fluoren-9-yl)methyl (S)-2-((S)-1-tert-butoxy-4-methyl-1-oxopentan-2-ylcarbamoyl)pyrrolidine-1-carboxylate (82361-41-9)

Conditions	Yield
With 2,3,5-trimethyl-pyridine; HATU In dichloromethane; N,N-dimethyl-formamide at 20℃; for 3h; Inert atmosphere;	99%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + cyanomethyl bromide (590-17-0) → (S)-tert-butyl 2-(cyanomethylamino)-4-methylpentanoate (1243692-13-8)

Conditions	Yield
With N-ethyl-N,N-diisopropylamine In acetonitrile at 20℃;	99%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + 1,1'-carbonyldiimidazole (530-62-1) + Fmoc-hydrazine hydrochloride → Fmoc-azaGly-Leu-OBut (872720-98-4)

Conditions	Yield
Stage #1: 1,1'-carbonyldiimidazole; Fmoc-hydrazine hydrochloride With N-ethyl-N,N-diisopropylamine In tetrahydrofuran at 20℃; for 1h; Cooling with ice; Stage #2: L-leucine tert-butyl ester hydrochloride In N,N-dimethyl-formamide at 20℃; for 18h; Cooling with ice;	99%
Stage #1: 1,1'-carbonyldiimidazole; Fmoc-hydrazine hydrochloride With N-ethyl-N,N-diisopropylamine In tetrahydrofuran at 35℃; for 1h; Cooling with ice; Stage #2: L-leucine tert-butyl ester hydrochloride In tetrahydrofuran; N,N-dimethyl-formamide at 35℃; for 18h; Cooling with ice;	99%

(5-nitro-1H-indol-1-yl)acetic acid (226901-50-4) + L-leucine tert-butyl ester hydrochloride (2748-02-9) → (S)-tert-butyl N-[(5-nitro-1H-indol-1-yl)acetyl] L-leucinate

Conditions	Yield
With O-(1H-benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate; triethylamine In dichloromethane at 20℃; for 4h; Inert atmosphere;	99%

(E)-2-hydroxyimino-propionic acid methyl ester (199434-50-9) + L-leucine tert-butyl ester hydrochloride (2748-02-9) → C13H24N2O4

Conditions	Yield
Stage #1: L-leucine tert-butyl ester hydrochloride With triethylamine In neat (no solvent) at 20℃; for 1h; Stage #2: (E)-2-hydroxyimino-propionic acid methyl ester With niobium(V) ethoxide In neat (no solvent) at 50 - 80℃; for 24h;	99%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + (S)-3-tert-butoxycarbonylaminobutyric acid (158851-30-0) → Boc-L-β-HoAla-L-Leu-O-t-Bu

Conditions	Yield
With pentamethoxy tantalum; 1-(Trimethylsilyl)imidazole In neat (no solvent) at 50℃; for 48h; Inert atmosphere; Sealed tube;	97%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + (S)-3-{[(tert-butoxy)carbonyl]amino}-5-(methylsulfanyl)pentanoic acid (244251-20-5) → Boc-L-β-HoMet-L-Leu-O-t-Bu

Conditions	Yield
With pentamethoxy tantalum; 1-(Trimethylsilyl)imidazole In neat (no solvent) at 40℃; for 48h; Inert atmosphere; Sealed tube;	97%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + L-N-t-butoxycarbonylpyroglutamic acid (53100-44-0) → Boc-pyroGlu-Leu-OtBu

Conditions	Yield
With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine In N,N-dimethyl-formamide at 0 - 20℃; for 12h;	96%
With benzotriazol-1-ol; triethylamine In N,N-dimethyl-formamide for 12h; Cooling with ice;	88%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + 2-[(2S)-N-[(benzyloxy)carbonyl]pyrrolidin-2-yl]-2-hydroxyacetic acid → (S)-2-[((S)-1-tert-Butoxycarbonyl-3-methyl-butylcarbamoyl)-hydroxy-methyl]-pyrrolidine-1-carboxylic acid benzyl ester

Conditions	Yield
With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine In N,N-dimethyl-formamide 1.) 0 deg C, 2 h, 2.) room temperature;	95.6%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + 2,2-dimethylcyclohexan-5-on-1-yl 2,3,4,6-tetra-O-lauroyl-1-thio-β-D-galactopyranoside (215312-92-8) → Dodecanoic acid (2S,3R,4S,5S,6R)-2-[5-((S)-1-tert-butoxycarbonyl-3-methyl-butylamino)-2,2-dimethyl-cyclohexylsulfanyl]-4,5-bis-dodecanoyloxy-6-dodecanoyloxymethyl-tetrahydro-pyran-3-yl ester (215313-22-7)

Conditions	Yield
With sodium cyanoborohydride In tetrahydrofuran; acetonitrile for 73h;	95%

2,5-dioxopyrrolidin-1-yl (2-(vinylsulfonyl)ethyl)carbonate (918822-70-5) + L-leucine tert-butyl ester hydrochloride (2748-02-9) → 2-(2-ethenesulfonyl-ethoxycarbonylamino)-4-methyl-pentanoic acid tert-butyl ester (918822-82-9)

Conditions	Yield
With sodium hydrogencarbonate In water; acetonitrile at 20℃; for 0.25h;	94%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + cyclohexan-2-on-1-yl 2,3,4,6-tetra-O-lauroyl-1-thio-β-D-galactopyranoside (215312-94-0) → Dodecanoic acid (2S,3R,4S,5S,6R)-2-[2-((S)-1-tert-butoxycarbonyl-3-methyl-butylamino)-cyclohexylsulfanyl]-4,5-bis-dodecanoyloxy-6-dodecanoyloxymethyl-tetrahydro-pyran-3-yl ester (215313-24-9)

Conditions	Yield
With sodium cyanoborohydride In tetrahydrofuran; acetonitrile for 73h;	93%

1-(4-fluorophenyl)-3-(R)-[2-(4-fluorobenzoyl)ethyl]-4-(S)-[4-(N-[(R)-1-carboxy-3-methylbutyl]carbamoylmethoxy)phenyl]azetidin-2-one (857506-64-0) + L-leucine tert-butyl ester hydrochloride (2748-02-9) → 1-(4-fluorophenyl)-3-(R)-[2-(4-fluorobenzoyl)ethyl]-4-(S)-{4-[N-((R)-1-{N-[1-(S)-(t-butoxycarbonyl)-3-(methyl)butyl]carbamoyl}-3-methylbutyl)carbamoylmethoxy]phenyl}azetidin-2-one (857506-66-2)

Conditions	Yield
With 4-methyl-morpholine; O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate In dichloromethane at 20℃; for 1h;	93%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + Nα-(allyloxycarbonyl)-Nε-(benzyloxycarbonyl)-L-Lysine → tert-butyl Nα-(allyloxy)carbonyl-Nε-(benzyloxycarbonyl)-L-Lysyl-L-Leucinate

Conditions	Yield
Stage #1: Nα-(allyloxycarbonyl)-Nε-(benzyloxycarbonyl)-L-Lysine With 4-methyl-morpholine; isobutyl chloroformate In tetrahydrofuran at -20℃; for 0.25h; Stage #2: L-leucine tert-butyl ester hydrochloride In tetrahydrofuran at 20℃; for 18h;	93%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + 2-Bromoacetyl bromide (598-21-0) → C12H22BrNO3 (1205615-78-6)

Conditions	Yield
With potassium carbonate In dichloromethane; water at -0.16 - 20℃;	91.8%

C22H26N6O8 (1026419-47-5) + L-leucine tert-butyl ester hydrochloride (2748-02-9) → C21H34N4O6 (958844-71-8)

Conditions	Yield
With N-ethyl-N,N-diisopropylamine In dichloromethane at 20℃; for 72h; Inert atmosphere;	91%

di(succinimido) carbonate (74124-79-1) + benzophenone hydrazone (5350-57-2) + L-leucine tert-butyl ester hydrochloride (2748-02-9) → tert-butyl ((2-diphenylmethylene)hydrazine-1-carbonyl)-L-leucinate

Conditions	Yield
Stage #1: di(succinimido) carbonate; benzophenone hydrazone In dichloromethane; N,N-dimethyl-formamide at 0 - 20℃; for 0.75h; Inert atmosphere; Stage #2: L-leucine tert-butyl ester hydrochloride With N-ethyl-N,N-diisopropylamine In dichloromethane; N,N-dimethyl-formamide at 0 - 20℃; for 16h; Inert atmosphere;	91%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + benzyl isothiocyanate (3173-56-6) → N-(benzylcarbamoyl)-leucine tert-butyl ester

Conditions	Yield
With diisopropylamine In dichloromethane at 0 - 20℃; for 0.5h;	90%

N-phenyl-N-methylcarbamoyl chloride (4285-42-1) + L-leucine tert-butyl ester hydrochloride (2748-02-9) → methyl (S)-4-methyl-2-{[methyl(phenyl)carbamoyl]amino}pentanoate

Conditions	Yield
With dmap; triethylamine In 1,2-dimethoxyethane for 2h; Inert atmosphere; Reflux;	90%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + (S)-2-[[[(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)methyl]diphenylsilanyl]methyl]-4-methylpentanoic acid (503066-39-5) → (S)-2-[(S)-2-[[[(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)methyl]diphenylsilanyl]methyl]-4-methylpentanoylamino]-4-methylpentanoic acid tert-butyl ester (561294-36-8)

Conditions	Yield
With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; N-ethyl-N,N-diisopropylamine In dichloromethane at 0 - 20℃; for 25h;	89%

1-(1-ethyl-propyl)-2-(tetrahydro-furan-2-ylmethyl)-1H-benzoimidazole-5-carboxylic acid (1586791-17-4) + L-leucine tert-butyl ester hydrochloride (2748-02-9) → (S)-2-{[1-(1-ethyl-propyl)-2-(tetrahydro-furan-2-ylmethyl)-1H-benzoimidazole-5-carbonyl]-amino}-4-methyl-pentanoic acid tert-butyl ester (1586791-16-3)

Conditions	Yield
With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; N-ethyl-N,N-diisopropylamine In N,N-dimethyl-formamide at 0 - 20℃; for 16h;	88%
Stage #1: 1-(1-ethyl-propyl)-2-(tetrahydro-furan-2-ylmethyl)-1H-benzoimidazole-5-carboxylic acid With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; N-ethyl-N,N-diisopropylamine In N,N-dimethyl-formamide at 0℃; for 0.25h; Stage #2: L-leucine tert-butyl ester hydrochloride With N-ethyl-N,N-diisopropylamine In N,N-dimethyl-formamide at 20℃; for 16h;	88%

Nα-(allyloxycarbonyl)-Nε-(benzyloxycarbonyl)-D-Lysine + L-leucine tert-butyl ester hydrochloride (2748-02-9) → tert-butyl Nα-(allyloxy)carbonyl-Nε-((benzyloxy)carbonyl)-D-Lysyl-L-Leucinate

Conditions	Yield
Stage #1: Nα-(allyloxycarbonyl)-Nε-(benzyloxycarbonyl)-D-Lysine With 4-methyl-morpholine; isobutyl chloroformate In tetrahydrofuran at -20℃; for 0.25h; Stage #2: L-leucine tert-butyl ester hydrochloride In tetrahydrofuran at 20℃; for 18h;	88%

L-3-phenyllactic acid (20312-36-1) + L-leucine tert-butyl ester hydrochloride (2748-02-9) → tert-butyl ((S)-2-hydroxy-3-phenylpropanoyl)-L-leucinate

Conditions	Yield
With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; N-ethyl-N,N-diisopropylamine In dichloromethane at 0 - 20℃;	88%

L-leucine tert-butyl ester hydrochloride (2748-02-9) + N-(tert-butoxycarbonyl)-N1-(4-iodobenzyl)-L-tryptophan → tert-butyl N-(tert-butoxycarbonyl)-N1-(4-iodobenzyl)-L-tryptophyl-L-leucinate

Conditions	Yield
With O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate; N-ethyl-N,N-diisopropylamine In acetonitrile at 20℃; for 18h;	88%

Downstream Products

• 58822-25-6 Leu-enkephalin 
• 215313-24-9 Dodecanoic acid (2S,3R,4S,5S,6R)-2-[2-((S)-1-tert-butoxycarbonyl-3-methyl-butylamino)-cyclohexylsulfanyl]-4,5-bis-dodecanoyloxy-6-dodecanoyloxymethyl-tetrahydro-pyran-3-yl ester 
• 215313-20-5 Dodecanoic acid (2S,3R,4S,5S,6R)-2-[3-((S)-1-tert-butoxycarbonyl-3-methyl-butylamino)-cyclohexylsulfanyl]-4,5-bis-dodecanoyloxy-6-dodecanoyloxymethyl-tetrahydro-pyran-3-yl ester 
• 215313-22-7 Dodecanoic acid (2S,3R,4S,5S,6R)-2-[5-((S)-1-tert-butoxycarbonyl-3-methyl-butylamino)-2,2-dimethyl-cyclohexylsulfanyl]-4,5-bis-dodecanoyloxy-6-dodecanoyloxymethyl-tetrahydro-pyran-3-yl ester 
• 723331-20-2 ZJ-43 
• 145902-56-3 tert-Butyl (4R,5S)-4-benzyl-5-(((2S)-1-(tert-butoxy)-4-methyl-1-oxopentan-2-yl)-carbamoyl)-2,2-dimethyl-1,3-oxazolidine-3-carboxylate 
• 1242168-90-6 N-[(2R,3R)-3-(tert-butoxycarbonyl)amino-2-hydroxy-4-phenylbutanoyl]-L-leucine tert-butyl ester