a(E)-1-Methoxy-1,3-butadiene and 1,1-Dimethoxy-1,3-butadiene in (4 + 2) Cycloadditions. A Mechanistic Comparison

• Published in: Journal of the American Chemical Society Vol. 118; no. 50; pp. 12555 - 12561
• Main Authors: Sustmann, Reiner, Tappanchai, Surajin, Bandmann, Heinz
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 18.12.1996; Amer Chemical Soc
• Subjects: Chemistry; Chemistry, Multidisciplinary; Physical Sciences; Science & Technology; ZWITTERION; <4+2>-CYCLOADDITIONS; DIELS-ALDER-REACTIONS; ETHYLENES; ELECTRON-DEFICIENT OLEFINS; TETRAMETHYLENES

The reactions of (E)-1-methoxy-1,3-butadiene (1) and 1,1-dimethoxy-1,3-butadiene (2) with a series of dienophiles of increasing electrophilicity are described. Stereochemical studies reveal that the cycloadditions of 1 are concerted processes, even for the most electron-deficient olefins dimethyl di...