C12H17NO 191.27

Benzamide,N,N-diethyl-3-methyl-.
N,N-Diethyl-m-toluamide [134-62-3].

Packaging and storage— Preserve in tight containers.

USP Reference standards á11ñ— USP Diethyltoluamide RS.

Identification,Infrared Absorption á197Sñ: solution;Assay preparationversus Standard preparationin Assay,in spectral region between 8µm and 15µm.

Specific gravity á841ñ: between 0.996and 1.002.

Refractive index á831ñ: between 1.520and 1.524.

Acidity— Dissolve 10.0g in 50mLof neutralized alcohol,add phenolphthalein TS,and titrate with 0.010Nsodium hydroxide:not more than 4.0mLof 0.010Nsodium hydroxide is required.

Water,Method Iá921ñ: not more than 0.5%.

Assay— Transfer about 200mg of Diethyltoluamide,accurately weighed,to a 10-mLvolumetric flask,dilute with carbon disulfide to volume,and mix to obtain the Assay preparation.Concomitantly determine the absorbances of the Assay preparationand of a Standard preparationof USP Diethyltoluamide RSin carbon disulfide having a known concentration of about 20mg per mLin 1-mm cells at the wavelength of maximum absorbance at about 14.1µm and at the wavelength of minimum absorbance at about 14.4µm,with a suitable IRspectrophotometer,using carbon disulfide as the blank.Calculate the quantity,in mg,of the meta-isomer of C12H17NOin the Diethyltoluamide taken by the formula: in which Cis the concentration,in mg per mL,of USP Diethyltoluamide RSin the Standard preparation,and AUand ASare the absorbances of the Assay preparationand the Standard preparation,respectively,at the wavelengths indicated by the subscripts.

Expert Committee:(PA7)Pharmaceutical Analysis 7

USP28–NF23Page 637

Phone Number:1-301-816-8394