Strained ring compounds

The polarization fiinctions are essential in strained ring compounds because they provide the angular flexibility needed to direct the electron density mto the regions between the bonded atoms. 

The strained-ring compound 1,1-dimethyl-l-silacyclobutane (which may be regarded as an olefin of organosilicon chemistry) reacts with diiron nonacarbonyl in benzene at 6°-20°C as shown in Eq. (100) (89). (There is here some analogy with the reactions of transition metal complexes with strained hydrocarbons, which often produce valence tautomerization.) The... 

See Other C-NITRO COMPOUNDS, STRAINED-RING COMPOUNDS... 

See other endothermic compounds, strained-ring compounds... 

Cyanocyclopropane (Cyclopropanecarbonitrile) [5500-21-0] v i CN Preparative hazard See 4-Chlorobutyronitrile Sodium hydroxide See other cyano compounds, strained-ring compounds c4h5n... 

See Other DIOXETANES, STRAINED-RING COMPOUNDS CYCLIC PEROXIDES... 

See Other STRAINED-RING COMPOUNDS 1918. Vinyl propionate... 

See other strained-ring compounds, acetylenic compounds, rotanes... 

Figure 3, together with Statement 6, clarifies some surprising results from different studies on strained ring compounds and culminates in the conclusion that Baeyer s theory is valid only for silicon rings [2],... 

Strained ring compounds undergo insertion of a low-valence metal complex to give metallacycles and the cycloaddition of metallacycles has a potential in synthesis, as described above. This method is useful in ring transformations of cyclobutenediones and cyclobutenones. 

We have discussed in this chapter the thermal pyrolyses of a number of strained ring compounds. In most of the cases considered there is good evidence that the processes are unimolecular. Where possible we have tried to suggest plausible transition complexes, and reaction paths, based on a consideration of such factors as the kinetic parameters, stereochemistry of the reaction and effect of substituents. In reactions of this type, the description of the transition complex is fraught with difficulties, since the absence of such things as solvent effects (which can be so helpfrd in bimolecular reactions) limit the criteria on which such descriptions may be based. Often two types of transition complex may be equally good at accounting for the observed data. Sometimes one complex will explain some of the data while another is better able to account for the remainder. It is probable that in many cases our representation... 

An illustrative example for photochemical cleavage of strained ring compounds is provided by Cossy and co-workers. The photoinduced single-electron... 

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