4377-82-6Relevant academic research and scientific papers
REDUCTION OF SULFONIUM AND SELENONIUM SALTS WITH SAMARIUM DIIODIDE
Kataoka, Tadashi,Iwama, Tetsuo,Shimizu, Hiroshi,Hori, Mikio
, p. 169 - 172 (2007/10/02)
Treatment of sulfonium and selenium salts with 2 equiv of a THF solution of samarium diiodide caused the reductive cleavage of the C-S or C-Se bonds in high yields.The bond cleavage took place regioselectively between the positive sulfur or selenium atom and the carbon atom with an electron-withdrawing group or a vinyl group.Some medium-sized cyclic sulfides or selenides were synthesized by this method.
Synthesis of Medium-Sized Cyclic Sulfides and Selenides by Crosspiece C-X Bond Cleavage of Bicyclic Onium Salts Bearing a Bridgehead Sulfur or Selenium Atom
Kataoka, Tadashi,Iwama, Tetsuo,Tsutsumi, Kazuhiro,Nakamura, Yoshihide,Matsumoto, Harutoshi,et al.
, p. 3153 - 3194 (2007/10/02)
Medium-sized cyclic sulfides 5a-5h and selenides 5i-5k were synthesized by reductive C-X bond cleavage of bicyclic sulfonium 4a-4h and selenonium salts 4i-4k, respectively.Reducing agents used were magnesium metal, sodium borohydride and samarium diiodide.Samarium diiodide reduction of simple sulfonium and selenonium salts 11a-11d, 15-18 was also carried out.Application of this method to the C-S bond cleavage of sulfonium salts 25a and 25b provided sulfur-containing medium-sized lactams 26a and 26b, respectively, in high yields.Treatment of the sulfonium salts 4f and 4g with a base gave an olefinic sulfide 33 and a cyclopropane derivative 31, respectively.The stereochemistry of the sulfonium, 4d and 4e, and selenonium salts, 4j and 4k, is discussed on the basis of the 13C NMR spectral data.
2-methylisoselenochromanium salts: Spectroscopic properties and reactions
Hori,Kataoka,Shimizu,Tsutsumi
, p. 779 - 780 (2007/10/02)
Some 2-methylisoselenochromanium salts were prepared. Proton nuclear magnetic resonance spectra in CDCI3 and electron impact mass spectra showed that the selenonium tosylate (4) and mesylate (5) are selenuranes and that the tetrafluoroborate (2
A New Method for Radical Generation: Reductive C-Se or C-S Bond Cleavage of Cyclic Onium Salts
Kataoka, Tadashi,Tsutsumi, Kazuhiro,Kano, Kenji,Mori, Kazuya,Miyake, Miho,et al.
, p. 3017 - 3025 (2007/10/02)
2-Methyl-3,4-dihydro-1H-2-benzoselenopyranium salt (1) was reduced by some metallic reagents or magnesium metal via the single-electron transfer (SET) process to give 2--toluene (2).Magnesium metal was a good SET reducing agent.Some other selenonium or sulphonium salts (7), (14), (22), (27) and (32) were similarly reduced by magnesium.Particularly, sonication accelerated the reductions. ε-Eneselenonium salt (43) was treated with activated magnesium to give a cyclised pyrrolidine derivative (44).
Cyclic Selenonium exo-Ylides (3,4-Dihydro-1H-2-benzoselenin-2-io)methanides; Syntheses and Reactions
Hori, Mikio,Kataoka, Tadashi,Shimizu, Hiroshi,Tsutsumi, Kazuhiro,Hu, Yong-Zhou,Nishigiri, Motoo
, p. 39 - 45 (2007/10/02)
Stable cyclic selenonium exo-ylides (3,4-dihydro-1H-2-benzoselenin-2-io)methanides; (5a-e) have been synthesized by reactions of 3,4-dihydro-1H-2-benzoselenin-2,2-dichloride (4) or N-(3,4-dihydro-1H-2-benzoselenin-2-io)toluene-p-sulphonamidate (6) and active methylene compounds.The ylidic nature and the stable configuration of (5a-e) were established on the basis of their spectral data.The reactions of ylides having acetyl group(s) (5a,b) with dimethyl acetylenedicarboxylate afforded the furan derivatives (8a,b) and (9a) and the dihydrobenzoselenin (3), while reactions of the ylides having no acetyl group, (5c-e), afforded the benzoselenonines (14c-e).The diacetylmethanide (5a) when heated gave the benzoselenepine (15), while (5c) when heated afforded the styrene derivative (18) and a tetrasubstituted ethylene (19).When heated, (5d) gave the rearranged product (22). 3,4-Dihydro-1H-2-benzoselenin-2-io)phenacylide (31) was generated by the reaction of the selenonium salt (24) with sodium hydride but was too unstable to be isolated.Thermal decomposition of (31) yielded (3), its counterparts (26-28), a styrene derivative (25), and a novel rearrangement product (29).
