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A new polymer, poly[5-(trimethylgermylmethyl)-1,3-cyclopentylenevinylene], was synthesized via ROMP of 5-(trimethylgermylmethyl)-2-norbornene in the presence of RuCl 3 .3H 2 O, RuCl 3 (PPh 3 ) 3 and RuCl 2 (PPh 3 ) 3 catalysts. The structure of the synthesized polymer was determined on the basis of IR, 1 H NMR and 13 C NMR spectra. The gas transport properties for this polymer have been studied.

This study was devoted to the use of the metathesis reaction for the synthesis of alkenes containing various reactive structural fragments (strained rings, metal-carbon bonds, oxygen-containing functional groups). Among the W, Mo and Re catalysts studied Re2O7/Al2O3PbEt4 and MoCl5/SiO2SnMe4SiCl4 turned out to be the most suitable. They were active toward a wide range of substrates bearing the fragments mentioned above, stable to catalyst poisons and able to be recovered. As a result, we accomplished the metathesis of alkylidene and alkenyl cycloalkanes, including 3- and 4-membered rings, which permitted us to develop a common method of synthesizing bi-and polycyclic hydrocarbons. The co-metathesis of cyclic C5-synthons results in the formation of isoprenoids and terpenoids. On the basis of co-metathesis with allylsilanes, a novel method for the lengthening of α-olefin chains and for double-bond transfer from the α to the β position has been demonstrated. Metathesis and co-metathesis reactions have been used to produce CH3(CH2)mCHCH(CH2)n X (where X = OAc, OH, CHO, m = 0–5, n = 4–10), which are used as insect pheromone components. Synthetic triglycerides formed by a co-metathesis reaction may be used for the production of various vegetable oil analogues.

Chemistry of cyclobutane hydrocarbons and their derivatives has been a subject of scientific attention science the beginning of the last century up to present time. The reasons of such a long attention is in special features of highly strained 4-membered ring structure and peculiar reactivity of cyclobutane compounds [1]. In application sense the compounds of this type demonstrate a range of interesting properties such as biological activity [2,3], capability to store energy [4,5], monomers activity to polymerization [1], etc. They are used as insecticides, in particular insect pheromone components [2,3], highly effective propellants [4.5] and energy accumulators [6].

Bulky substituents, such as α-naphthyl and ferrocenyl groups, do not inhibit the metathesis of allylsilanes on a Re2O7/Al2O3-SnBu4, catalyst system. Metathesis represents a preparative synthetic method for the synthesis of 1,4-bis(α-napthyl-dimethylsilyl)- and 1,4-bis(ferrocenyldimethylsilyl)but-2-enes.

Metathesis of spirocyclo[2.2.1]hept-2-ene-7,1'-cyclopropane and its co-metathesis with norbornene and 5-decene on homogeneous and heterogeneous catalytic systems were carried out for the first time. The reactions were shown to proceed with retention of the spirosystem.

By cometathesis of α-olefins with allylsilanes and subsequent desilanization of the products obtained, the lengthening of the hydrocarbon chain of α-olefins has been achieved.

The feasibility was demonstrated for the efficient metathesis of phecyltolyl- and benzylallylsilanes on an alumorhenium catalyst promoted by tetrabutyltin. The metathesis of aryldimethylallylsilanes or aralkyldimethylallylsilanes is a preparative method for the synthesis of 1,4-bis(aryldimethylsilyl)-2-butenes or 1,4-bis(aralkyldimethylsilyl)-2-butenes.

Methylen-cyclobutan (I) wird durch den Katalysator Rheniumoxid/Aluminiumoxid (enthaltend 15% Re) bei 35°C zu Bicyclobutyliden (II) und Athylen (III) disproportioniert, wobei (III) standig aus dem Reaktionsgemisch entfernt wird.

The feasibility was demonstrated for the efficient metathesis of phecyltolyl- and benzylallylsilanes on an alumorhenium catalyst promoted by tetrabutyltin. The metathesis of aryldimethylallylsilanes or aralkyldimethylallylsilanes is a preparative method for the synthesis of 1,4-bis(aryldimethylsilyl)-2-butenes or 1,4-bis(aralkyldimethylsilyl)-2-butenes.