(CAS NO.: ), which is also known as , 1,1-diphenyl-, could be produced through the following synthetic routes.

In a 2-l. three-necked flask, fitted with a separatory funnel, reflux condenser, and stirrer, is placed 27 g. (1.1 atoms) of magnesium turnings. A mixture of 30 g. of bromobenzene and 70 cc. of dry ether is run in and the flask warmed gently until the reaction becomes rapid. Stirring is then started, and the vessel is surrounded by a dish of cold water. A mixture of 151 g. of bromobenzene (total: 181 g., 1.15 moles) and 380 cc. of dry ether is run in at such a rate as to cause vigorous refluxing; when the addition is complete (one hour) the whole is stirred for ten minutes.

After the flask has been cooled by immersion in ice water, 44 g. (0.5 mole) of dry ethyl acetate in an equal volume of ether is added over a period of twelve minutes. The cooling bath is removed and stirring is continued for ten minutes. When the reaction flask has again been cooled by the ice-water bath, a previously prepared ammonium chloride solution is added, very slowly at first, over a period of ten minutes, during which a pasty solid separates.

The ether layer is decanted into a separatory funnel, and to it is added a 50-cc. ether extract of the pasty residue. The ether is removed by dropping the solution into a 500-cc. round-bottomed flask attached to a condenser and immersed in an oil bath heated to 210–215°. The flask is removed from the oil bath, cooled, and disconnected from the condenser; 100 cc. of 20 per cent sulfuric acid is added. The flask is fitted with a reflux condenser, and the contents are boiled for one hour. The aqueous layer is now removed, and the residual oil, without being washed, is distilled at a pressure of about 30 mm. and a bath temperature of about 210°. At first a low-boiling fraction consisting of bromobenzene (12–14 g.) and traces of water distils, after which the diphenylethylene comes over as a colorless liquid, the last portions being slightly yellowish. The brownish residue contains polymerization and decomposition products. On redistillation, the pure hydrocarbon boils at 113°/2 mm.. The yield is 60–66 g. (67–70 per cent of the theoretical amount based on ethyl acetate) .