Shengule, Sudhir RRyder, GregoryWillis, AnthonyPyne, Stephen G2015-12-100040-4020http://hdl.handle.net/1885/69252The acid catalysed cyclization reactions of tethered furan-4,5- dihydroxypyrrolid-2-ones and furan-4,5-diacetoxypyrrolid-2-ones, via their corresponding N-acyliminium ion intermediates, have been studied. In the case of the tethered furan-3,4-dihydroxypyrrolid-2-one 16, having a two carbon tether, the linearly fused tricyclic compound 18 was formed with high cis selectivity (cis/trans=84:16) when BF3·OEt2 was used as a catalyst. However, when the cyclization reaction was carried out on the related tethered furan-4,5-diacetoxypyrrolid-2-one 17, the linearly fused tricyclic compound 20 was formed as a single diastereoisomer with trans selectivity. In contrast, the attempted cyclization of the tethered furan-4,5-dihydroxypyrrolid- 2-one 26, having a one carbon tether, did not result in formation of the corresponding linearly fused tricyclic system, instead it formed the dimer 29 as a single diastereoisomer. Cyclization reactions of the related tethered furan-4,5-diacetoxypyrrolid-2-one 27 also failed to give the corresponding linearly fused tricyclic system or macrocycle.Keywords: 1 [2 (furan 2 yl)ethyl] 4,5 dihydroxypyrrolidin 2 one; 1 [2 (furan 2 yl)ethyl] 5 oxopyrrolidin 2,3 diyl diacetate; 1,5 bis(furan 2 ylmethyl)octahydro [1,4]dioxino[2,3 b:5,6 b']dipyrrole 2,6 dione; 7 oxo 4,5,7,8,9,9a hexahydrofuro[2,3 g]indolizin 9 yl acet201210.1016/j.tet.2012.10.0142016-02-24