Reaction of (2-Nitro- and 2-Bromo-2-nitroethenyl)phosphonates with 1,3-Cyclohexadiene
作者:N. A. Anisimova、A. A. Kuzhaeva、G. A. Berkova、L. I. Deiko、V. M. Berestovitskaya
DOI:10.1007/s11176-005-0365-0
日期:2005.7
Specific features of the reactions of bis(chloroethyl) 2-nitro- and 2-bromo-2-nitroethenylphosphonates with 1,3-cyclohexadiene were studied. It was found that the reaction with 2-nitroethenylphosphonate occurs stereoselectively and provides bis(2-chloroethyl) endo-(3-nitrobicyclo[2.2.2]oct-5-en-2-yl)phosphonate. 2-Bromo-2-nitroethenylphosphonate under the same conditions gives a mixture of the endo and exo isomers of the corresponding nitrobicyclooctenes. Enhanced tendency of adducts derived from gem-bromonitroethenyl-phosphonates for intramolecular transformations, such as dehydrohalogenation and aromatization, under the cycloaddition conditions was revealed.
研究了 2-硝基和 2-溴-2-硝基乙烯基膦酸双(氯乙基)酯与 1,3-环己二烯反应的具体特征。研究发现,与 2-硝基乙烯基膦酸盐的反应是立体选择性的,反应生成了双(2-氯乙基)内(3-硝基二环[2.2.2]辛-5-烯-2-基)膦酸盐。在相同条件下,2-溴-2-硝基乙烯基膦酸盐可生成相应的硝基双环辛烯内、外异构体的混合物。研究发现,在环加成条件下,由溴硝基乙烯基膦酸盐衍生的加合物发生分子内转化(如脱氢卤化和芳香化)的趋势增强。