41678-29-9Relevant academic research and scientific papers
Structure-Odor Correlation, XIX. Synthesis and Olfactory Properties of Various Racemic Theaspirones, Ketoedulans and Edulans
Weyerstahl, Peter,Meisel, Thomas
, p. 415 - 428 (2007/10/02)
Starting from the cheap isophorone derivative 1 and the alkynols 2-4, we could prepare the key intermediates 9-11 via addition reaction (--> 5-7) and hydrogenation.Ring closure of 9-11 led to the theaspirone (C) and/or ketoedulan (E) series, depending on the reaction conditions used and the steric situation at C-2.By tratment of 9 with tosyl chloride/pyridine the theaspirone derivative 13 was formed exclusively, whereas 10a, b were converted into mixtures of 14a, b together with the ketoedulan derivatives 20a, b; the crowded 11 did not react at all.By treatment of 9-11 with hydrochloric acid/acetone 19-21 were readily obtained.Several hydrogenation and dehydration steps under various conditions led to the theaspirones 16-18, to the ketoedulans 26a, b and 27, and to the edulans 39a and 40b. - Olfactory evaluation of the theaspirones 16 (harsh, green), 17a (floral, fruity) and 18 (weak, woody) shows the drastic influence of the steric situation at C-2.The ketoedulans 26a and 27 smell weak, woody.Evaluation of both odor and flavor of 39a and 40b exhibits mostly woody, camphoraceous and fruity tonalities. - Key Words: Theaspirone derivatives / Edulan derivatives / Terpenes / Odor
New Syntheses of Edulans and Theaspiranes from α-Inone
Etoh, Hideo,Ina, Kazuo,Iguchi, Masanobu
, p. 2871 - 2876 (2007/10/02)
New syntheses of edulans and theaspiranes are described.The key step involves the cyclization of 4-(2',6',6'-trimethyl-2'-hydroxy-3'-cyclohexen-1'-yl)-butan-2-ol (7) and 4-(2',6',6'-trimethyl-1',2'-dihydroxy-3'-cyclohexen-1'-yl)-butan-2-ol (8) derived from α-ionone.The diol (7) and triol (8) were cyclized with acetic acid into the corresponding tetrahydropyran derivatives ; the latter two compounds were dehydrated to edulan I and II (13a, 13b).On treatment with tosyl chloride in pyridine, however, triol (8) gave spiro-compounds (11a, 11b and 12); (11a and 11b) were easily converted to cis- and trans-theaspirone by oxidation and 5,6-erythro-6-hydroxy-dihydrotheaspiranes (15a and 15b) by reduction.
