DIBENZYL CARBONATE Chemical Properties

Melting point:

29-33 °C(lit.)

Boiling point:

180-190 °C2 mm Hg(lit.)

Density 

1.1515 (rough estimate)

refractive index 

1.5485

Flash point:

>230 °F

solubility 

Sparingly Soluble (0.099 g/L) (25°C).

form 

powder to lump

color 

White to Almost white

Sensitive 

Air Sensitive

BRN 

1882864

CAS DataBase Reference

3459-92-5(CAS DataBase Reference)

EPA Substance Registry System

Carbonic acid, bis(phenylmethyl) ester (3459-92-5)

Safety Information

Hazard Codes 

Xn

Risk Statements 

21/22

Safety Statements 

36

WGK Germany 

3

TSCA 

Yes

HS Code 

29209090

MSDS

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DIBENZYL CARBONATE Usage And Synthesis

Chemical Properties

Colorless low melting solid

Uses

Ionic liquids can effectively accelerate slow N-benzylation reactions utilizing dibenzyl carbonate as an alkylating reagent. Dibenzyl carbonate (DBzlC) has been used to benzylate phenylacetonitrile, benzyl phenylacetate and phenol. Selective N, N-dibenzylation of primary aliphatic amines was carried with dibenzyl carbonate in the presence of phosphonium salts.

Preparation

To a stirred solution of benzyl alcohol (0.216 g, 2.00 mol), tributylphosphine (0.303 g, 1.50 mmol), and CyTMG (0.394 g, 2.00 mmol) in DMF (2.00 mL), CO2 was added at room temperature. After 15 min, tetrabromomethane (0.663 g, 2.00 mmol) was added, the reaction vessel was sealed, and the contents were stirred for 2 h. Thereafter, the reaction mixture was diluted with ethyl acetate, washed successively with 0.5 m aqueous HCl and saturated aq. NaHCO3 solution, and dried over Na2SO4. Diphenylmetha- nol was added to the organic solution as an internal standard and the yield of dibenzyl carbonate was determined from the relative integrals of a methylene peak of the carbonate and a methine peak of diphenylmethanol in the 1H NMR spectrum of the ethyl acetate solution. Dibenzyl carbonate, prepared by a larger scale reaction of CO2 with benzyl alcohol (1.08 g, 10.0 mmol), was isolated by column chromatography (cyclohexane/ethyl acetate, 50:1) in 67.3% yield (0.816 g).

Synthesis Reference(s)

The Journal of Organic Chemistry, 60, p. 6205, 1995 DOI: 10.1021/jo00124a044

General Description

Dibenzyl carbonate (DBC) is commonly used as a benzylating agent. Dimethyl carbonate and excess of benzyl alcohol undergoes transesterification in the presence of CsF/α-Al₂O₃ (cesium fluoride/aluminum oxide) to form DBC. The formation of N,N-dibenzyl derivatives by the reaction of primary aliphatic amines with DBC in the presence of phosphonium salts has been investigated.

DIBENZYL CARBONATE(3459-92-5)Related Product Information

• Benzyl chloroformate
• Ethyl methyl carbonate
• Calcium carbonate
• SODIUM CARBONATE, MONOHYDRATE
• Strontium carbonate
• Guanidine carbonate
• HOLMIUM CARBONATE
• LANTHANUM CARBONATE
• Potassium phthalimide
• Vinylene carbonate
• Propylene carbonate
• DIBUTYL CARBONATE
• Chloromethyl pivalate
• Titanium ethoxide
• Ethylene carbonate
• PHENYL FORMATE
• Diisopropyl carbonate
• Carbonic acid dihexyl ester