Spiropentane, polymerization

Polymerization. Monomers. The cyclopropane type monomers are prepared either by addition of the dichlorocarbene or by the Simmons-Smith reaction on the corresponding olefins. Most of these compounds have been described. Spiropentane is prepared by the Applequist method (I, 2), by the reaction of zinc with C(CH2Br)4 in alcohol in the presence of ethylenediaminetetraacetic acid (EDTA). This hydrocarbon is purified until a single NMR signal is obtained at t = 9.28. 

Polymerization of Spiropentane. The study of polymerization by opening of the three carbon ring has given a picture of the reactivity of spiropentane with respect to various catalysts. 

This paper deals with the polymerization of several purely hydro-carbonated and gem-dihalocyclopropanic monomers. The influence of conjugation between a cyclopropane and one double bond, and the influence of the conjugation between two cyclopropanic groups is shown for several monomers, such as spiropentane, vinyl gem-dihalocyclopro-pane, and bicyclononene. 

Polymerization of Spiropentane, Methylenecylobutane, and Bicyclo-propyle. One compound in the spirane hydrocarbon series is especially worthy of attention—namely spiropentane (Afs), which is an isomer of both isoprene and methylenecyclobutane (M9) see Equation 13. From a structural point of view, if one considers that spiropentane is the linear combination of the p orbital and the sp orbital associated with each ring of spiropentane, four equivalent sp hybrid orbitals may be formed. Under these conditions, spiropentane constitutes a highly p-type unsaturated entity that is thus especially suitable for polymerization. 

Polymerization of Spiropentane. The preparation of spiropentane (19) is important, since other compounds are formed (for example,... 

Polymerization of Spiropentane by Metal-Halide Complexes. Heterogeneous-phase polymerization with trialkylaluminum metal-halide... 

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