Novel Type Elimination Reactions of Sulfoxides Bearing Several Heteroaromatics: Trapping of Sulfines with 2,3-Dimethyl-1,3-butadiene
作者:Hiroyuki Morita、Masahiro Takeda、Toshiaki Yoshimura、Takayoshi Fujii、Shin Ono、Choichiro Shimasaki
DOI:10.1021/jo990610l
日期:1999.9.1
Diels-Alder reaction of the diene with the sulfines formed initially by the thermal decomposition of the sulfoxides. The rate acceleration and the improvement of the yield by addition of 1.5 equiv of triethylamine, especially in the case of ethoxycabonylmethyl sulfoxide 1c, was observed. The cis-trans selectivity for sulfine cycloadducts was also studied by NMR spectrometry. The reactions of alpha-substituted
先前我们报道了通过热解带有一些杂芳族化合物的苯甲亚砜生成的新型硫代醛。在2,3-二甲基-1,3-丁二烯存在下于100摄氏度下,在2,3-二甲基-1,3-丁二烯存在下,带有其他杂环的亚砜(1a,b和2a-4a)的热分解导致意外的产物6 -取代的5,6-二氢-3,4-二甲基-2H-噻喃-1-氧化物(5a,b)。这些产物被认为是通过二烯的Diels-Alder反应与最初通过亚砜的热分解而形成的亚砜形成的。通过加入1.5当量的三乙胺,观察到速率加快和产率提高,特别是在乙氧基羰基甲基亚砜1c的情况下。还通过NMR光谱法研究了磺基环加合物的顺-反选择性。