Abstract: Described is a process for the preparation of hydrocarbyl metal halides, such as alkyl tin chlorides, in which a reaction between the metal in its metallic state and a hydrocarbyl halide is catalyzed by a dihydrocarbyl sulfoxide or a dihydrocarbyl formamide in the presence of a hydrocarbyl metal halide and wherein the pressure of the reaction vessel is varied during the reaction.

Abstract: Methyltin trichloride and dimethyltin dichloride are prepared in high yields without pressure using pentavalent organophosphorous dihalides as a catalyst. The catalyst may be reused for multiple sequential preparations of the methyltin chlorides.

Abstract: This invention is directed to novel catalysts characterized as compounds of tin or zinc containing a direct metal-nitrogen bond. The novel catalysts are derived from a primary or secondary amine such as an alkyl amine, a heterocyclic amine, an aromatic amine, etc. The amine is reacted with a tin compound such as a tin chloride, a tin bromide, a tin oxide, or a tin alkoxide. Alternatively, the amine may be reacted with a zinc halide, a zinc alkoxide or an organozinc compound.In another aspect of the present invention, the novel catalysts are used to catalyze the reaction of an acrylate or methacrylate ester with an amine in order to prepare N-substituted acrylamides or methacrylamides in good yield and with high selectivity.

Abstract: Ammonium stannates of the formula[(R.sup.1).sub.a (R.sup.2).sub.b N(R.sup.3).sub.c (R.sup.4).sub.d ].sub.n.sup..sym. [(R.sup.7).sub.q SnX.sub.r Y.sub.t ].sub.w.sup.n.crclbar.(I)in which the symbols R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.7, X, Y, a, b, c, d, n, q, r, t and w are as defined in the description, are effective biocides. They can be used both for the protection of materials and for protecting crop plants. Their good solubility in water and their low volatility are particularly valuable properties.