81206-67-9Relevant academic research and scientific papers
Diels-Alder Reactions of (Trifluoromethyl)ethene and (Trifluoromethyl)styrenes with Functionalized Butadiens
Ojima, Iwao,Yatabe, Momoko,Fuchikami, Takamasa
, p. 2051 - 2055 (1982)
The-Alder reactions of (trifluoromethyl)ethene (1) with 2-(trimethylsiloxy)buta-1,3-diene (2), 2--1,3-butadiene (4), and 1-methoxy-3-(trimethylsiloxy)buta-1,3-diene (6) were carried out to give the corresponding cycloadducts in 17-38percent yields.It was found that the former two cycloadducts were a mixture of para (major) and meta (minor) isomers, while the latter was the para isomer exlusively.Similary, β-(trifluoromethyl)-4-(methoxycarbonyl)styrene (9) and β-(trifluoromethyl)-4-nitrostyrene (10) were allowed to react with 4 and 6, giving the corresponding cycloadducts in 56-90percent yields.The regioselectivity of the reaction on using 6 as the diene turned out to be extremely high, leading to the formation of only one regioisomer.The substituent effect of the trifluoromethyl group in the Diels-Alder reaction in terms of regioselectivity is discussed.
