GB703954A - A new or improved method for the preparation of alkyl titanates - Google Patents

Abstract

An alkyl titanate is obtained by admixing titanium tetrachloride, an alcohol having at least two carbon atoms in the molecule, and liquid ammonia in a closed system, the ammonia being present in amount at least equal to that required to react with the chloride ions released from the tetrachloride plus that required to dissolve all the ammonium chloride formed by the reaction, and separating the liquid alkyl titanate layer from the liquid ammonia-ammonium chloride layer, the entire process being carried out in the anhydrous state. The titanium tetrachloride, alcohol and liquid ammonia may be mixed in any order but it is preferred to admix the titanium chloride and the alcohol and then add the resulting mixture to the liquid ammonia. The reaction is preferably carried out at about room temperature. The alcohol used is preferably a primary or secondary, monohydric, non-substituted aliphatic alcohol containing 2 to 20 carbon atoms and a moderate excess of the alcohol may be employed. It is desirable to remove as much as possible of the liberated hydrogen chloride from the mixture of titanium tetrachloride and alcohol before admixture with the ammonia and this may be effected by passing a stream of non-reacting gas such as dry air through the mixture. In examples: (1) titanium tetrachloride is added to a stoichiometrically equivalent amount of n-butanol at such a rate as to maintain the temperature at 45-50 DEG C. and the resulting mixture is then mixed with butanol so as to give an excess of the latter. The mixture is then blown into a closed water-jacketed reactor containing liquid ammonia under pressure at 22 DEG C. and when the addition is complete butyl titanate is recovered from the lower liquid layer; (2) the procedure is similar to that in (1) except that a stream of air is bubbled through the initial mixture of metal chloride and butanol to sweep out a further portion of the hydrogen chloride formed, (3) as in (2) except that the air blown mixture is reacted with the liquid ammonia without the addition of further butanol; (4) titanium tetrachloride is added dropwise to 5-ethyl-nonanol-2, the latter being present in stoichiometric excess, and the resulting yellow liquid is then added under pressure to a reactor containing liquid ammonia under pressure, two layers are formed, tetra (5-ethyl-2-nonyl) titanate being obtained from the lower layer; (5) tetra (2-(1, 3, 3-trimethyl-butyl)-5, 7, 7-trimethyloctyl) titanate is obtained from the corresponding alcohol by a procedure similar to that used in (4).