- Unexpected conversion of vinyl sulfoxides into carbonyl compounds by means of iodotrimethylsilane
-
The unexpected and previously unknown TMSI-promoted conversion of α,β- unsaturated sulfoxides into carbonyl compounds and disulfides is described. It occurs in good yields under mild conditions. The examples provided support the generality and efficiency of this procedure which acts as a good method for removing the sulfinyl group with the advantage of transforming the vinyl sulfoxides into carbonyl compounds. (C) 2000 Elsevier Science Ltd.
- Aversa, Maria C.,Barattucci, Anna,Bonaccorsi, Paola,Bruno, Giuseppe,Giannetto, Placido,Policicchio, Manuela
-
-
Read Online
- Asymmetric Diels-Alder Reaction of Optically Active α-(2-exo-Hydroxy-10-bornyl)sulfinylmaleimides and its Application to Optically Active 5-Functionalised Pyrrolines via Retro-Diels-Alder Reaction
-
Optically pure sulfinylmaleimides 1 have been synthesized.The Diels-Alder reactions of the sulfoxides 1 with various dienes showed high diastereoselectivity.Regioselective reduction of the adducts 4c and 6c followed by desulfination afforded the γ-hydroxy
- Arai, Yoshitsugu,Matsui, Makoto,Fujii, Akihito,Kontani, Tohru,Ohno, Toshiyuki,et al.
-
-
- A New Resolution Procedure for the Preparation of Both (R)-(+)- and (S)-(-)-4-tert-Butoxycyclopent-2-enone from Racemic 4-tert-Butoxycyclopent-2-enone and Conversion of (R)-(+)-Butoxycyclopent-2-enone into (R)-(+)-4-Acetoxycyclopent-2-enone. A New Method for the Determination of the ...
-
(1S)-(-)-10-Mercaptoisoborneol undergoes conjugate addition to (+/-)-4-tert-butoxycyclopent-2-enone in methanol containing N,N,N',N'-tetramethylethylenediamine to give a 1:1 mixture of diastereomers of 3-tert-butoxy-4-heptanyl)methyl>thio>cyclopentanone in 93-95percent yield.The mixture is converted by m-chloroperbenzoic acid into the corresponding sulfoxide mixture.The (3R,4R,RS)-sulfoxide isomer, whose absolute configuration has been determined by X-ray crystallography, crystallizes cleanly from this mixture in an enantiomeric yield of 76percent from the corresponding sulfide.It is decomposed on silica gel to generate (R)-(+)-4-tert-butoxycyclopent-2-enone, with an enantiomeric purity of >/- 99.9percent in 92percent yield from the sulfoxide, and 10-thiodiisobornyl 10'-sulfoxide.Similarly, the (S)-(-)-enone is prepared from (1R)-(+)-10-mercaptoisoborneol.The (+/-) and the (R)-(+)-enone, respectively, are converted by a catalytic amount of FeCl3 in acetic anhydride into (+/-) and (R)-(+)-4-acetoxycyclopent-2-enone (with an enantiomeric purity of >/- 99.9percent) in 80percent yield.The enantiomeric purity of the products was assessed through their treatment with (-)-10-mercaptoisoborneol and analysis of the adducts by HPLC and 400-MHz 1H NMR spectroscopy.
- Eschler, Bart M.,Haynes, Richard K.,Ironside, Michael D.,Kremmydas, Steve,Ridley, Damon D.,Hambley, Trevor W.
-
p. 4760 - 4766
(2007/10/02)
-
- Synthesis and Asymmetric Diels-Alder Reaction of Dimethyl ('d-Isoborneol-10-sulphinyl')maleate: Novel Route to Key Intermediates for Synthesis of Some Carbocyclic Nucleosides and Terpenoids
-
The chiral sulphoxide 1 was synthesized from 10-mercaptoisoborneol via diastereoselective oxidation.The dienophile 1 reacted with cyclopentadiene in the presence of a Lewis acid to give the adducts 7 and 8 with high diastereoselectivity (ca. 100percent).D
- Arai, Yoshitsugu,Hayashi, Kazuya,Matsui, Makoto,Koizumi, Toru,Shiro, Motoo,Kuriyama, Kaoru
-
p. 1709 - 1716
(2007/10/02)
-
- An Enantiodivergent Synthesis of Fused Bicycloheptane Lactones via an Asymmetric Diels-Alder Reaction
-
An enantiodivergent synthesis of the bicycloheptane lactone (2) is described, by regioselective reduction of the Diels-Alder adducts (3) and (4) with di-isobutylaluminium hydride followed by reductive elimination of the chiral auxiliary, 10-mercaptoisoborneol (9) through reaction with samarium(II) iodide.
- Arai, Yoshitsugu,Matsui, Makoto,Koizumi, Toru
-
p. 1233 - 1234
(2007/10/02)
-