Abstract: The present invention provided an improved method for preparing a boratabenzene derivative. The invention includes an improved preparation of 1,4-pentadiyne, 1-haloboracyclohexa-2,5-diene, and 1-methylboracyclohexa-2,5-diene intermediates. These compounds are chemically labile and are not directly isolated from solution. Furthermore, the invention discloses an improved preparation of 1,1-dialkylstannacyclohexa-2,5-diene, another intermediate useful for preparing boratabenzene derivatives.

Abstract: The present invention relates to a metallocene compound of the formula I which is suitable for olefin polymerization ##STR1## where M is a metal of group IVb, Vb or VIb of the Periodic Table.X are each a hydrogen atom, a halogen atom or a C.sub.1 -C.sub.40 -radical OR.sup.4 or NR.sup.4.sub.2, where R.sup.4 are a C.sub.1 -C.sub.20 hydrocarbon radicalm and p are 1, 2 or 3,n is 1 or 2,L each a .pi. ligand which coordinates to the central atom M,M.sup.2 are each a silicon atom, a germanium atom or a tin atom,R.sup.1 are a C.sub.1 -C.sub.20 -radical,R.sup.2 are a C.sub.1 -C.sub.20 -radical or a .pi. ligand which coordinates to the central atom M,A are each a bidentate C.sub.1 -C.sub.40 -hydrocarbon group,Z are each a boron atom, a silicon atom, a germanium atom or a tin atom,R.sup.3 are each a hydrogen atom or a C.sub.1 -C.sub.20 -radical,o is zero, 1 or 2,Hal are each a halogen atom, andwhere n is 1 if R.sup.2 is a .pi. ligand which coordinates to the central atom M and n is 2 if R.sup.2 is a C.sub.1 -C.sub.

Abstract: The invention relates to novel aromatic fluorine-containing organotin compounds of the formula {(F.sub.5 C.sub.6 RCO.sub.2 SnBu.sub.2).sub.2 O}.sub.2 and {(F.sub.5 C.sub.6 RCO.sub.2).sub.2 SnBu.sub.2 } wherein R is CH.sub.2, CH.dbd.CH or a single bond between the phenyl ring and the CO.sub.2 group, and Bu is a butyl group; as well as to anti-tumour compositions containing as an active ingredient one or more of these compounds.

Abstract: Solutions of triorganotin lithium are described having low residual concentrations (preferably less than 2,000 ppm) of halide. These are produced by a two-step process.Triorganotin halide is reacted with lithium to produce hexaorgano ditin and a precipitate of lithium halide. The lithium halide precipitate is removed by filtration and/or use of highly concentrated reaction conditions. Then the hexaorgano ditin is further reacted with lithium to form the triorgano substituted tin lithium. The lithium halide is less soluble in hot tetrahydrofuran (THF) and/or more concentrated solutions. THF is a preferred solvent for the reaction. The low-temperature reactions described result in low amounts of inactive and/or undesirable byproducts. These triorganotin lithium compounds are useful as anionic initiators that result in polymers with terminal tin compounds, e.g., triorganotin, attached to the terminal end of the polymer where initiation occurred.

Abstract: A method for coupling tin-containing molecules via a Sn--Sn bond is described. The invention employs dehydrocondensation to link the Sn atoms of two molecules to form tin dimers as well as novel high molecular weight organotin polymers. In a preferred embodiment, catenated tin polymers are formed from hydrostannane precursors in the presence of a suitable metal catalyst. A particularly preferred method involves coupling dialkylstannane monomers in the presence of a metallocene catalyst to form polystannanes. Preferred catalysts include electropositive metals, such as Zr and Hf. The polystannanes are photolabile, decomposing readily under room light conditions.

Abstract: The present invention relates to a method of preparing hexaalkyl distannanes by converting bis-[trialkyltin]oxide with a stabilized solution of sodium borohydride in alcohol, preferably methanol, in the presence of an inert solvent.

Abstract: Organometal-containing styrene derivatives of the formula I ##STR1## in which, for example, M is Si, X is 0, R.sup.1 and R.sup.2 are hydrogen, R.sup.4 to R.sup.6 are each methyl, a is zero and R.sup.7 is hydrogen or methyl, and organometal-containing compounds of the formula VII ##STR2## in which M and R.sup.1 to R.sup.6 are, for example, as defined above and Y is, for example, 4-nitrophenoxy, are valuable starting materials for the preparation of organometal-containing polymers. The polymers are suitable for the preparation of photoresists which can be developed under dry conditions, such as are required in the production of structured images, particularly in microelectronics.

Abstract: Dibasic lead-fatty acid salts are synthesized in a melt reaction between plumbous oxide and fatty acids in the presence of magnesium, calcium, and/or aluminum compounds. The salts are useful as stabilizers for halogen-containing polymers.

Abstract: Dibasic lead-fatty acid salts and mixtures thereof with neutral lead-fatty acid salts are synthesized in a melt reaction using a free-hydroxyl organic compound as a catalyst/initiator. The resulting products are useful as stabilizers for halogen-containing polymers.