404596-47-0Relevant academic research and scientific papers
A new 3-(phenylseleno)allylic cation: Its regioselective C-C bond formation reaction with nucleophiles
Hibino, Masaru,Koike, Tomoko,Yoshimatsu, Mitsuhiro
, p. 1078 - 1083 (2007/10/03)
Highly useful C-C bond formation using 2-ethoxy-3-(phenylseleno)prop-2-enal acetal 2 was examined with various Lewis acids. The reaction of 2 with the silyl enol ether in the presence of BF3·Et2O, ZnBr2, or SnBr4 regioselectively provided (Z)-3,4-diethoxy-5-(phenylseleno)pent-4-enophenone 5a in high yields. On the other hand, the reaction with other Lewis acids such as EtAlCl2 or SnCl4 gave 5-(phenylseleno)- 6 or non-selenopentane-1,4-dione 7, respectively. Novel prop-2-enal acetals 2-4 and 13-15 reacted with various nucleophiles to give pent-4-enophenones 5a,b, 10a, 12, and 16-18, S-ethyl pent-4-enoate 5b, alkylated vinylic sulfide 10b, 3-pentenenitrile 5d, and 10c. A versatile pent-4-enophenone 5a could be converted to tetrahydrofuran 20 and penta-2,4-dienophenone 19, the Diels-Alder reactions of which with dienophiles gave the adducts 24 and 25.
