[99-33-2] · C7H3ClN2O5 · 3,5-Dinitrobenzoyl Chloride · (MW 230.57)
Physical Data: mp 69-71 °C; bp 196 °C/11 mmHg.
Solubility: sol ether; reacts with water and protic solvents.
Form Supplied in: 98% pure form as yellow solid (2% impurity as carboxylate); widely available.
Purification: recrystallization from carbon tetrachloride/petroleum ether (40-60 °C) or from benzene.
Handling, Storage, and Precautions: lachrymator; corrosive and moisture sensitive. Avoid inhalation. Store in sealed tube or under petroleum ether.
3,5-Dinitrobenzoates, prepared by the acylation of a hydroxy group with 3,5-dinitrobenzoyl chloride, have been utilized in solvolysis studies,1 SN2´ displacement of propargylic alcohols,2 and derivatization of alcohols for characterization purposes.3,4 A variety of functional groups are stable under the benzoylation conditions (eqs 1 and 2). An alternative preparation of 3,5-dinitrobenzoates entails the direct coupling of 3,5-dinitrobenzoic acid and an alcohol using an activating reagent such as 1-Ethyl-3-(3´-dimethylaminopropyl)carbodiimide Hydrochloride (eq 3).2b
The 3,5-dinitrobenzoate esters of alcohols are often crystalline derivatives and have been used for characterization purposes.3 For example, selective benzoylation of the secondary hydroxy group of an isomer of 25-hydroxyvitamin D3 affords the corresponding crystalline 3,5-dinitrobenzoate derivative (eq 4).3b
The chromatographic separation of the enantiomers of alcohols, using a chiral stationary phase, is enhanced by the preparation of the corresponding 3,5-dinitrobenzoate derivatives.4
3,5-Dinitrobenzamides are useful derivatives of amines for characterization purposes (eqs 5 and 6). The 3,5-dinitrobenzamides of amines have been particularly useful for the chromatographic separation of amines, amino acids, and amino alcohols using chiral stationary phases.4,5
Gary A. Sulikowski & Michelle M. Sulikowski
Texas A & M University, College Station, TX, USA