Institut für Organische Chemie, Fakultät für Chemie und Mineralogie, Universität Leipzig, Johannisallee 29, 04103 Leipzig, Germany.
J Org Chem. 2011 Mar 4;76(5):1499-502. doi: 10.1021/jo102413u. Epub 2011 Jan 18.
Tetrahydrofuran derivatives can be obtained by cyclofunctionalization of homoallylic alcohols bearing a terminal double bound by using [hydroxy(tosyloxy)iodo]benzene (HTIB, Koser's reagent) in the presence of a catalytic amount of I(2) (20 mol %) in MeOH under mild conditions. This transformation is an overall 5-endo-trig cyclization, which occurs by two different pathways. The first is a 4-exo-trig cyclization followed by ring expansion, whereas the second is an electrophilic addition followed by a 5-endo-tet cyclization.
四氢呋喃衍生物可以通过在温和条件下，在催化量的碘（20 摩尔%）存在下，使用[羟基（对甲苯磺酰氧基）碘]苯（HTIB，Koser 试剂）对带有末端双键的偕丙醇进行环官能化来获得。这种转化是一个整体的 5-endo-trig 环化，它通过两种不同的途径发生。第一种是 4-exo-trig 环化，然后是环扩张，而第二种是亲电加成，然后是 5-endo-tet 环化。
