56859-91-7Relevant articles and documents
Enantioselective Oxidative (4+3) Cycloadditions between Allenamides and Furans through Bifunctional Hydrogen-Bonding/Ion-Pairing Interactions
Villar, Laura,Uria, Uxue,Martínez, Jose I.,Prieto, Liher,Reyes, Efraim,Carrillo, Luisa,Vicario, Jose L.
supporting information, p. 10535 - 10538 (2017/08/22)
BINOL-based N-trifluoromethanesulfonyl phosphoramides catalyze the enantioselective (4+3) cycloaddition between furans and oxyallyl cations, the latter being generated in situ by oxidation of allenamides. The chiral organic phosphoramide counteranion is proposed to engage in the activation of the oxyallyl cation intermediate through cooperative hydrogen-bonding and ion-pairing interactions, enabling an efficient chirality transfer that provide the final adducts with high diastereo- and enantioselectivities. Remarkably, the reaction shows a wide substrate scope that includes a variety of substituted allenamides and furans.
Microwave-mediated claisen rearrangement followed by phenol oxidation: A simple route to naturally occurring 1,4-benzoquinones. The first syntheses of verapliquinones A and B and panicein A
Davis, Christopher J.,Hurst, Timothy E.,Jacob, Aouregan M.,Moody, Christopher J.
, p. 4414 - 4422 (2007/10/03)
The naturally occurring 1,4-benzoquinones 2-methoxy-6-propyl-1,4- benzoquinone (1), 2-methoxy-6-pentyl-1,4-benzoquinone (primin 2), 2-methoxy-6-pentadecyl-1,4-benzoquinone (3), 2-methoxy-6-heptadecyl-l,4- benzoquinone (dihydroirisquinone, pallasone B; 4) were synthesized by a simple protocol involving microwave accelerated Claisen rearrangement of allyl ethers 10, followed by hydrogenation of the side chain alkene, and oxidation to the quinone. The Claisen-based methodology was extended to the first synthesis of the marine benzoquinones verapliquinones A and B (5 and 6), and panicein A (7). Isoarnebifuranone (9) was also synthesized by a similar strategy.
Structure-Odor Correlation, XXI. Olfactory Properties and Convenient Synthesis of Furans and Thiophenes Related to Rose Furan and Perillene and Their Isomers
Weyerstahl, Peter,Schenk, Anja,Marschall, Helga
, p. 1849 - 1854 (2007/10/03)
Starting from 3-bromofuran (1) or 3-bromothiophene (2) via alkylation in 2-position (-> 3-8) followed by the corresponding second alkylation in 3-position, we obtained rose furan (9), rose thiophene (10), and their analogs 11-16.From the α,β-unsaturated esters 17-20 by hydrogenation (-> 21-24), DIBAH reduction (-> 25-28), and Wittig reaction, perillene (29), thioperillene (30), and their analogs 29-36 were obtained.Olfactory evaluation showed that the difference between the furans and thiophene derivatives is remarkably small, particularly for perillene (29) compared with thioperillene (30), and their analogs.Also the influence of position and structure of the side chain is lower than expected within the compared compounds 9-36. - Keywords: Rose furan / Perillene / Furans / Thiophenes / Structure-odor correlation / Odoriferous substances