Anisaldehyde Test

Other Reagents Sulfuric acid and acetic acid. 

Comments Commercially available. Detects aromatic and aliphatic aldehyde groups. Provides an orange to red color. 

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Colour Reactions. Rochelmeyer (1939) has provided a list of colour reactions given by solasodine and solasodiene (solanosodine), with reagents usually applied to the sterols, and Briggs et al. have found that when concentrated sulphuric acid (1 mil) is carefully added to a solution of solasonine or solasodine in hot alcohol (1 mil) a characteristic, intense, greenish-yellow fluorescence is produced, a reaction which is not given by solanine or solanidine. They have also found that intense colours are formed when solasonine or solasodine is mixed with resorcinol, or one of a variety of aldehydes, and boiled with concentrated hydrochloric acid. Colours are also produced with this test by cholesterol, digitonin, jacobine carbazole, pyrrole, or nicotine, the most intense colours being formed with p-hydroxybenzaldehyde or anisaldehyde. 

The value of q2vs calculated from the viscosity and density of anisaldehyde at the various temperatures is compared to the value derived from the light-scattering spectra in Table 12.2.2. The accuracy of the fitted parameters A2, R, and q2vs was tested by ... 

Suitable samples for silica columns are acetanilide, short-chain phthalates such as dimethyl phthalate or diethyl phthalate and anisaldehyde. They exhibit weak interaction with the silica surface that prevents tailing. Good retention factors are obtained with methylene chloride-based or hexane-based mobile phases with small amounts of methanol, isopropanol,. or acetonitrile. Examples are hexane with 0.5% acetonitrile, methylene chloride with 0.5% isopropanol, or methylene chloride with 0.1% methanol. To ensure rapid equilibration with the mobile phase, the mobile phase should be half-saturated with water. For a 5-nm column, a good linear velocity in these solvents is between 2 and 3 mm/s. Nitroaromatics are used sometimes as samples for the testing of silica columns, but they may exhibit peak tailing depending on the pretreatment of the silica. 

The new fimctionalized resin 200a was first tested in the phenylation of / -tolualdehyde and / -anisaldehyde in toluene at 10°C using 5 mol% of the catalyst and the dependance of enantioselectivity on the level of functionalisation was studied (entries 1-6, Table 13). The... 

Visualisation of the substance zones can be carried out on normal silica gel layers by using cone, sulphuric acid, if necessary with addition of aldehyde. The anisaldehyde-sulphuric acid reagent (No. 11) is preferable. The fluorescein-bromine test (No. 118) and the antimony(V)-... 

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