1965-38-4Relevant articles and documents
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Banks,R.M.,Maskill,H.
, p. 1506 - 1513 (1976)
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La Londe,Batelka
, p. 445,446 (1964)
Stereospecific SN2' Reactions of exo-4-Substituted 3-Halogenbicyclooct-2-enes
Maskill, H.,Wilson, Alan A.
, p. 39 - 42 (1982)
Stereochemically pure samples of exo-bicyclooctan-2-ol are obtained from hydrolysis followed by hydrogenation-hydrogenolysis of exo-3,4-dihalogenobicyclooct-2-enes.Attempted tosylation of the intermediate hydroxy-halides in these reactions by the Tipson procedure gave only exo-4-chloro-3-halogenobicyclooct-2-enes.No inversion of configuration was detected in the reactions of exo-3,4-dihalogenobicyclooct-2-enes with sodium halides in aprotic dipolar solvents.These results lead to the conclusion that the SN2' reaction in this system occurs upon covalent substrates with retention of relative configuration but inversion of absolute configuration.
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Sauers,R.R. et al.
, p. 983 - 987 (1965)
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Hydroalumination of alkenes by the LiAlH4*3AlBr3 system
Gorobets, E. V.,Shitikova, O. V.,Lomakina, S. I.,Tolstikov, G. A.,Kuchin, A. V.
, p. 1573 - 1578 (2007/10/02)
The hydroalumination of a series of alkenes and some fused aromatic hydrocarbons by the LiAlH4*3AlBr3 system in low-polar solvents was studied.Alkenes with mono-, di-, tri-, and tetraalkyl substituted, mono- and diaryl substituted double bonds and anthracene react at room temperature to give the corresponding dibromoaluminoalkanes in high yields.Benzylidenefluorene, tetraphenylethylene, naphthalene, and phenanthrene do not undergo hydroalumination under these conditions.Camphene, bicyclooct-2-ene, and norbornene afford the corresponding organoaluminum compounds with high stereoselectivity.Oxidation and halo- and acyldemetallation of the resulting alkyl- and arylalanes were carried out.
Differential Bridging in the Solvolysis of Epimeric Bicyclic Sulfonates. Norbornanes, Part 17
Grob, Cyril A.,Waldner, Adrian,Zutter, Ulrich
, p. 717 - 729 (2007/10/02)
The solvolysis rates and products of the 2-exo- and 2-endo-norbornyl, bicyclooct-8-yl, bicyclonon-2-yl, bicyclooct-6-yl, bicyclooct-2-yl and bicyclonon-6-yl p-toluenesulfonates 10-15, respectively, are reported.The exo/endo rate ratios for these epimeric secondary tosylates in 80percent EtOH varied from 1125 for 11 to 1.6 for 15.The relative rates varied between 2278 for exo-10 and 4E-3 for endo-11.The hydrolysis products were mainly rearrenged alcohols and olefins.The unrearrenged alcohols from the exo-tosylates were formed with complete or predominant retention of configuration, whereas those derived from the endo-tosylates were mostly inverted.These results confirm the hypothesis that relative rates, as well as products, are largely determined by the degree of bridging between the cationic center and a dorsal C-atom in the transition state and in the resulting ion pairs.Since bridging is a directed bonding interaction, it is subject to the same angle and conformational strains as ordinary covalent bonds.But bridging requires less geometrical change than the formation of normal bonds and of nonclassical ions.
