| Name | Acetic anhydride |
|---|---|
| Chinese Name | 醋酐 |
| Type | 脂肪族化合物 |
| CAS No | 108-24-7 |
| Physical Properties | M 102.1, b 138℃, d420 1.082, nD25 1.3904. |
| Method for Purification | Adequate purification can usually be achieved by fractional distillation through an efficient column. Acetic acid can be removed by prior refluxing with CaC2 or with coarse Mg filings at 80-90℃ for 5 days, or by distillation from a large excess of quinoline (1% AcOH in quinoline) at 75 mm pressure. Acetic anhydride can also be dried by standing with Na wire for up to a week, removing the Na and distilling it under vacuum. (Na reacts vigorously with acetic anhydride at 65-70℃). Dippy & Evans [J Org Chem 15 451 1950] let the anhydride (500g) stand over P2O5(50g) for 3 hours, then decanted it and stood it with ignited K2CO3 for a further 3 hours. The supernatant liquid was distilled and the fraction b 136-138℃ was further dried with P2O5 for 12 hours, followed by shaking with ignited K2CO3, before two further distillations through a five-section Young and Thomas fractionating column. |
| Relative literature | PDF |
Extended Information