97309-63-2Relevant academic research and scientific papers
Formation and Reactivity of Hydroxy-substituted γ- and δ-Lactones
Bardili, Burkhart,Marschall-Weyerstahl, Helga,Weyerstahl, Peter
, p. 275 - 300 (2007/10/02)
Hydrolysis of the esters (Z)-6-8 with H2SO4 in acetone leads to a mixture of γ- (17-19) and δ-Lactones (13-15) in various ratios.From (Z)-9 the rearrangement product 20 is obtained.By reaction of (Z)-6-9 with Et2O-BF3 the δ-lactones 13-16 are formed only.The saturated esters 10-12 hydrolyze to give a γ/δ-lactone mixture 24-26/21-23.Changing to BF3, favors the rearrangement 10 -> 30. - The δ-lactones 13-16 are not dehydrated with POCl3 in pyridine but chlorinated to afford 31-34.On heating in pyridine 33 and 34 are dehydrochlorinated to give the α-pyrones 38 and 39.Dechlorination with zinc in acetic acid leads to β,γ-unsaturated δ-lactones (31,35 -> 44; 32 -> 45; 33 -> 46).The mixture of saturated γ/δ-lactones 21b/24a/24b yields with POCl3 the elimination products 50 and 51, while a 23/26a/26b mixture furnishes the unsaturated γ-lactones 53a, b, and 54 as well as the chlorinated δ-lactones 55.Hydrogenation (44 -> 56; 45 -> 57; 46 -> 58; 51-> 59; 53/54 -> 60) gives the saturated parent compounds.
