Verfahren zum Herstellung von neuen Pyrimidin-thion-Verbindungen

Extreme pressure lubricant additives are novel C8- 22 alkyl pyrimidine-2-thiones, in the concentration range of 0.1-20% by weight. Specific compositions are (a) 3.5% by weight lard oil; 96.5% by volume mineral oil; and 1.5% by weight of N-dodecyl, N-coco or N-C11- 15-alkyl pyrimidine-2-thione; also (b) 3.0% by volume lard oil; 5% by weight of one of the thiones mentioned above; and a base of paraffin oil. The additives impart extra lubricity under the conditions of extreme pressure.ALSO:Novel compounds of the formula where R is an aliphatic C8- 22 hydrocarbon group, are prepared by reacting a >C=S containing compound with a diamine of the formula RNH-(CH2)3-NH2, wherein R is as defined above, between 0-80 DEG C. to yield the corresponding dithiocarbamic acid which is subsequently cyclized by heating between 90 DEG -200 DEG C. The reaction may be performed in a solvent such as ethanol, methanol, butanol, isopropanol, CHCl3, ethylene chloride, CCl4 or diethyl ether. The solvent is evaporated before cyclization. The compounds are of use as extreme pressure lubricant oil additives (see Division C5).