Synthesis of Some 2,5-Substituted 7-Oxabicyclo[2.2.1]heptanes: Stereochemistry of Diels-Alder Adducts of a 3-Alkylfuran
作者:Richard L. Jarvest、Simon A. Readshaw
DOI:10.1055/s-1992-26279
日期:——
From the Diels-Alder reaction of 3-benzylfuran with acrylonitrile were isolated three of the four possible isomeric adducts, 5(or 6)-benzyl-7-oxabicyclo [2.2.1]hept-5-ene-2-endo (or exo)-carbonitriles 6-8, with the 5-benzyl-2-endo-carbonitrile 7 predominating. The two 5-benzyl isomers, 7 and 8, were further elaborated to compounds 2-endo-aminomethyl-5-endo-benzyl-7-oxabicyclo [2.2.1]heptane hydrochloride (11) and 5-endo-benzyl-7-oxabicyclo [2.2.1]heptane-2-exo-carboxamidine hydrochloride (12).
从 3-苄基呋喃与丙烯腈的 Diels-Alder 反应中分离出四种可能的异构加合物中的三种,5(或 6)-苄基-7-氧杂双环 [2.2.1]庚-5-烯-2-内型(或外型) )-甲腈 6-8,其中 5-苄基-2-内甲腈 7 占主导地位。 两种 5- 苄基异构体 7 和 8 进一步精制为化合物 2-内型-氨基甲基-5-内型-苄基-7-氧杂双环[2.2.1]庚烷盐酸盐 (11) 和 5-内型-苄基-7-氧杂双环[2.2.1]庚烷-2-外型-甲脒盐酸盐(12)。