- Syntheses of perillene and natural congeners via Li2CuCl4-catalyzed cross-coupling reaction of allylic carbonates
-
Perillene is an essential ingredient in a Chinese patent drug and features some fascinating biological activities. We present herein an efficient pathway to perillene that hangs on the cross-coupling reaction of allylic carbonates with furfuryl Grignard r
- Sun, Ya-Nan,Wang, Qi,He, Ling,Wang, Xi,Li, Wei-Dong Z.
-
-
- Sulfur monoxide transfer from peri -substituted trisulfide-2-oxides to dienes: Substituent effects, mechanistic studies and application in thiophene synthesis
-
Three peri-substituted trisulfide-2-oxides are prepared by treatment of 1,8-naphthalene dithiols with thionyl chloride and pyridine. The 1,2,3-trithiane-2-oxide ring adopts a sofa conformation in the solid state, with a pseudoaxial oxygen and evidence of ring strain (peri-interaction). Heating the trisulfide-2-oxides in the presence of a diene results in formal sulfur monoxide (SO) transfer to form unsaturated cyclic sulfoxides, along with a recyclable 1,8-naphthalene disulfide. The presence of o-methoxy or o-tert-butyl substituents on the naphthalene ring lowers the temperature and increases the rate at which SO transfer occurs. Trapping experiments and kinetic studies are consistent with the generation of triplet SO, followed by in situ trapping by diene. Transfer of SO also occurs upon irradiation at room temperature, but yields of sulfoxide are lower. Dehydration of the sulfoxides under Pummerer conditions gives thiophenes, including the naturally occurring thioperillene. Two dienes form thiophenes directly under the SO transfer conditions. The methodology is applied in a formal synthesis of the antiplatelet medication Plavix.
- Grainger, Richard S.,Patel, Bhaven,Kariuki, Benson M.,Male, Louise,Spencer, Neil
-
supporting information; experimental part
p. 5843 - 5852
(2011/06/22)
-
- A novel recyclable sulfur monoxide transfer reagent
-
(matrix presented) Trisulfide 2-oxide 11 has been prepared from disulfide 9 via reduction to the corresponding dithiol and subsequent trapping with thionyl chloride. Heating trisulfide oxide 11 in the presence of dienes results in transfer of sulfur monoxide to form cyclic unsaturated sulfoxides 13 in good to excellent yields, along with recovery of disulfide 9. A Pummerer reaction can be used to convert the cyclic sulfoxides into thiophenes.
- Grainger, Richard S.,Procopio, Alberto,Steed, Jonathan W.
-
p. 3565 - 3568
(2007/10/03)
-
- Structure-Odor Correlation, XXI. Olfactory Properties and Convenient Synthesis of Furans and Thiophenes Related to Rose Furan and Perillene and Their Isomers
-
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
- Weyerstahl, Peter,Schenk, Anja,Marschall, Helga
-
p. 1849 - 1854
(2007/10/03)
-
- Selective Alkylation and Allylation of Allylic Halides by Tetraorganoidates: Regio- and Stereo-selective Synthesis of Rosefuran and Sesquirosefuran
-
Tetraalkylindanes regioselectively alkylate allylic bromides at the α-carbon.In this way, 1,5-dienes have been regio- and stereo-selectively synthesized by the allyl-allyl coupling of allylic bromides and allylic indates, including rosefuran 1 and sequirosefuran 3.
- Araki, Shuki,Jin, Shun-Ji,Butsugan, Yasuo
-
p. 549 - 552
(2007/10/02)
-
- Substituted thiophenes, flavouring and perfuming compositions, perfumed products containing them
-
Flavouring and perfume compositions as well as flavoured foodstuffs and allied products and also perfumed products characterized by a content of one or more substituted thiophenes with the formula wherein none, one or two of the dotted lines represent a double bond with the proviso that no cumulated double bonds are present.
- -
-
-
- REGIO-CONTROLLED PRENYLATION AND GERANYLATION OF 3-FURYLMETHYLMAGNESIUM BROMIDE. SELECTIVE SYNTHESES OF 3-SUBSTITUTED FURANOID AND 2-SUBSTITUTED 3-METHYLFURANOID TERPENES.
-
Coupling reactions of 3-furylmethylmagnesium bromide with prenyl and geranyl diethyl phosphates gave 2-substituted 3-methylfurans, rosefuran and sesquirosefuran, as the main products. When the reactions were carried out in the presence of a catalytic amount of copper(I) iodide, normal coupling occurred and 3-substituted furans, perillene and dendrolasin, were formed in good yields. The related naturally occurring 3-substituted thiophene, 3-(4-methyl-3-pentenyl)thiophene, was also synthesized from 3-thienylmethylmagnesium bromide and prenyl diethy phosphate.
- Araki,Butsugan
-
p. 1446 - 1449
(2007/10/02)
-
- Chemistry of Hop Constituents. Part 43. Cyclic Polysulphides and a Thiophen from Myrcene, and their Occurrence in the Essential Oil of Hops
-
Steam-distilled hop oils (from hops dressed on the bine with sulphur) have been shown to contain 3-(4-methylpent-3-enyl)thiophen (2) and 4-(4-methylpent-3-enyl)-1,2-dithiacyclohex-4-ene (4) together with the corresponding trisulphide (5) and tetrasulphide (6) but not the monosulphide (3).All five compounds are obtainable from myrcene (1) and sulphur and have been characterised, and some alternative syntheses and related work are described.
- Elvidge, John A.,Jones, Stephen P.,Peppard, Terence L.
-
p. 1089 - 1094
(2007/10/02)
-