Antiklopf-Zubereitungen

摘要

1,112,921. Tetrahydrocarbon leads. ETHYL CORPORATION. 11 May, 1965 [11 May, 1964 (2)], No. 19925/65. Heading C2J. [Also in Division C5] An anti-knock composition comprises a mixture of tetrahydrocarbon leads of the following formulµ: PbR 4 , PbR 3 R1, PbR1 3 R 2 , PbRR1 3 and PbR1 4 wherein R is an alkyl group, preferably of 1 to 4 carbon atoms and R1 is an alkenyl group preferably of 2 to 10 carbon atoms. The relative amount of each compound in the mixture is according to a statistical distribution of the hydrocarbon groups among the tetrahydrocarbon leads or within 7% thereof. There are preferably two to four different groups R and R1. R1 may constitute 25 to 75% of the groups R and R1. The composition may be prepared by contacting a compound of the formula PbR n R1 (4-n) , n= 1, 2 or 3, or a mixture of at least two compounds of the formula PbR x R1 (4-x) , x=0, 1, 2, 3 or 4 with a catalyst the compounds being such that both R and R1 are in the mixture. The catalyst may be used in the amount 0À1 to 5% wt. of the total weight of reactants and may be an activated aluminosilicate, e.g. zeolite, or active Al 2 O 3 , AlCl 3 , (Et) 2 Zn, ZaF 2 , (Me) 2 AlCl, ZrCl 4 , PCl 3 , FeCl 3 or Me 3 Al 2 Cl 3 . The reaction may be carried out from below 0‹ C. up to the decomposition temperature of the tetrahydrocarbon lead, e.g. at 20‹ to 70‹ C. The composition may also be prepared by reacting a Pb salt, Pb oxide or sulphide under anhydrous conditions with a mixture of at least two Grignard reagents, the mixture containing both R and R1. This reaction temperature may be 20‹ to 120‹ C., the pressure may be 0À2 atm. to 2000 p.s.i. The composition is recovered by washing, filtering and distilling the filtrate. A desensitizing agent, e.g. toluene, naphthalene and alkylated phenols, may be added before recovery. The Grignard reagents may be methyl or ethyl magnesium chloride and vinyl magnesium chloride.