Diazodiphenylmethane and Monosubstituted Butadienes: Kinetics and a New Chapter of Vinylcyclopropane Chemistry
作者:Akihiro Ohta、Klaus Dahl、Rainer Raab、Jochen Geittner、Rolf Huisgen
DOI:10.1002/hlca.200890081
日期:2008.5
structures of the vinylcyclopropanes 7, 9, and 12 are established by NMR spectra and oxidation. A cyclopropyl carbinyl cation is made responsible for the isomerization of 12, R=Ph, Me, by acetic acid to 4-substituted 1,1-diphenylpenta-1,3-dienes 25 and 29; TsOH at 200° converts 25 further to 9,10-dihydro-9-methyl-10-phenyl-9,10-ethanoanthracene (27). Thermal rearrangement of 7, 9, and 12 at 200–300° produces
重氮二苯甲烷(DDM)仅在C(3)C(4)键上进行环取代成1取代的buta-1,3-二烯。在室温下,最初形成的4,5-二氢-3 H-吡唑2的N 2损失比环加成反应快,并为乙烯基环丙烷衍生物7和9提供了在C(1)C(2)键上的结构保留。2-取代的丁二烯与DDM在C(3)C(4)键处反应生成12 ; 异戊二烯,然而,得到3,4- / 1,2-产品中的86比:14 DDM是亲核1,3-偶极:1-Cyanobutadiene反应比1-methoxybuta -1,3-二烯快400倍(DMF ,40°)。日志 ķ 2为添加六个1取代的丁二烯示出了具有线性相关σ p(哈米特)和ρ = + 2.9; 日志 ķ 2的5个2取代的丁二烯线性相关于塔夫脱的σ我(ρ = + 1.7)。乙烯基环丙烷7、9和12的结构通过NMR光谱和氧化来建立。使环丙基羰基阳离子负责将乙酸12(R = Ph,Me)异构化为4-取代的1