39778-83-1Relevant academic research and scientific papers
Samarium(II) iodide-mediated intramolecular conjugate additions of alpha,beta-unsaturated lactones.
Molander, Gary A,St Jean Jr., David J
, p. 3861 - 3865 (2007/10/03)
Samarium(II) iodide, in the presence of catalytic amounts of nickel(II) iodide, has been used to promote intramolecular conjugate additions of alkyl halides onto alpha,beta-unsaturated lactones. This process has been shown to be applicable to a number of alpha,beta-unsaturated lactones, including tetrasubstituted olefins, and has been demonstrated to be quite general for the formation of saturated bicyclic and tricyclic lactones. The method presented herein provides a mild, efficient process to form structurally complex lactones from simple precursors.
Synthesis of 1-Substituted cis-Bicyclooctanones through Cycloadditions of Dichloroketene to Alkenes. Structural Characterization of Cycloadducts by Oxa-Ring Expansion
Jeffs, Peter W.,Molina, Gerado,Cass, Malcom W.,Cortese, Nicholas A.
, p. 3871 - 3875 (2007/10/02)
The cycloaddition of dichloroketene to a series of 1-substituted cyclohexanes is shown to proceed in a highly regio- and stereospecific manner.The structures of the cycloadducts were determined by reductive dechlorination to the cyclobutanones, and the structures and stereochemistry of the latter as cis-bicyclooctan-7-ones (4) were established by an oxa-ring expansion to the corresponding cis-octahydrobenzofuran-2-ones (6).The structures of the lactones 6 were established by 1H and 13C NMR studies which further indicated that these compounds exist in conformation 6a rather than 6b.The success of the regio- and stereospecific cycloaddition of dichloroketene to the 1-substitutd cyclohexenes discussed is found to be critically dependent on utilizing the zinc dehalogenation procedure for its in situ generation.Additional examples of the cycloaddition of dichloroketene to indene, 1,4,-dihydronaphthalene and 1,2-dihydronaphthalene is also presented.
