Anisole Infrared Spectrum

Fig. 3.25 Infrared spectrum of anisole recorded as a liquid film.

These compounds are suggested if sulphur is present. If nitrogen is also present the compound may be an aminosulphonic acid. The infrared spectrum will show absorption at 3400-3200 cm -1 (OH str.) and 1150 and 1050 cm-1 (S=0 str. in a sulphonic add) or at 1090cm-1 (S=0 str. in a sulphinic acid). For derivative preparations for sulphonic acids see Section 9.6.26, p. 1284. The presence of an aromatic sulphinic add may be further confirmed by dissolving in cold concentrated sulphuric add and adding one drop of phenetole or anisole when a blue colour is produced (Smiles s test), due to formation of a para-substituted aromatic sulphoxide. The reaction is ... 

Potassium dihydrobis(l-pyrazolyl)borate, m.p. 171-172°C., is a white crystalline solid, highly soluble in water and polar solvents. It may be recrystallized from anisole, but with large solubility losses. The infrared spectrum has a complicated BH2 stretch multiplet in the 2200-2500-cm.-1 range. It is very soluble in water and alcohols, but the ligand undergoes slow solvolysis, and solutions should be made up just before use. 

Potassium hydrotris(l-pyrazolyl)borate is a white crystalline solid. As prepared, m.p. 185-190°C., it is suitable for the synthesis of transition-metal chelates. Its melting point may be raised to 188-189°C. by recrystallization from anisole but this entails large solubility losses. Its infrared spectrum has a sharp BH peak at 2500 cm.-1. This salt is very soluble in water, alcohols, and polar organic solvents. It is stored best as a solid, and its reactions should be carried out on freshly prepared solutions. 

Thermal Decomposition Compound VII (101.7 mg) was heated neat at 155°C (boiling anisole). An infrared spectrum (KBr pellet) of... 

To a cooled (-25°C) 100-ml flask previously flame-dried and blanketed with nitrogen is added via a syringe a solution of 0.17 gm (0.4 mmole) of tetraphenyl titanate and 0.02 ml (0.2 mmole) vanadyl trichloride in 55 ml of chlorobenzene. Then a 3-ml portion (3.0 mmole) of a 1 M solution of di-ethylaluminum chloride in heptane to which a molar equivalent of anisole has been added is injected into the flask. Then 5 ml (0.045 mole) hexatriene is added via a syringe and stirred at -25°C for 24 hr. The resulting viscous solution is carefully quenched by pouring into cold, acidified (3% HCl) ethanol to precipitate the polymer. The polymer is washed with cold, acidified ethanol, absolute ethanol, and then dissolved in benzene to remove insolubles. The polymer (2.75 gm 78%) is stable in the benzene solution ([ /]inh 0-5% in benzene at 30°C of 0.61). The polymer on drying becomes crosslinked but is stable in solution. The infrared spectrum of 1,6-polyhexatriene is shown in Fig. 1. 

Infrared spectrum of anisole (neat liquid, salt plates). 

At the instructor s option, determine the boiling point of your product using the microboiling-point method (Technique 13, Section 13.2). Determine both the infrared and the NMR spectra (proton and carbon-13). The infrared spectra may be determined neat, using salt plates (Technique 25, Section 25.2), except for the product from anisole, which is a solid. For this product, one of the solution spectrum techniques (Technique 25, Section 25.6) should be used. The proton NMR spectra can be determined as described in Technique 26, Section 26.1. Deuteriochloroform is also an excellent solvent for all the carbon-13 samples as described in Technique 27, Section 27.1. Any residual methylene chloride appears at 5.3 ppm in the proton spectrum and at 54 ppm in the carbon spectrum. 

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