95581-35-4Relevant academic research and scientific papers
First Synthesis and Reactivities of Isolable Dithiiranes and Their 1-Oxides
Ishii, Akihiko,Akazawa, Toru,Ding, Meng-Xin,Honjo, Takanari,Maruta, Teruo,Nakamura, Shin-Ya,Nagaya, Hidenori,Ogura, Miho,Teramoto, Katsuhiko,Shiro, Motoo,Hoshino, Masamatsu,Nakayama, Juzo
, p. 509 - 523 (2007/10/03)
The reaction of the 6-exo-oxide of 2,2,4,4-tetramethyl-1,5-diphenyl-6,7-dithiabicyclo[3.1.1]heptane (2) with 2KHSO5·KHSO4·K2SO4 gave the first isolable dithiirane oxide, (1RS, 3SR)-3-phenyl-3-(1,1,3,3-tetramethyl-4-oxo-4-phenylbutyl)dithiirane 1-oxide (1), while the 6-endo-oxide of 2 gave both 1 and its (1RS, 3RS)-isomer 10. Under similar reaction conditions, 2 yielded the first isolable, unoxidized dithiirane, 3-phenyl-3-(1,1,3,3-tetramethyl-4-oxo-4-phenylbutyl)dithiirane (3). The dithiirane 3 was also obtained by treatment of 2 with NaOCl-NaClO4. The X-ray structure analyses were performed for 1, 3, and 10. Treatment of unsymmetrical 8,8-dimethyl-1,9-diphenyl-10,11-dithiatricyclo[7.1.1.0 2,7]-undeca-2,4,6-triene with NaOCl-NaClO4 gave 3-[1-(o-benzoylphenyl)-1-methylethyl]-3-phenyldithiirane selectively in good yield. However, 1,3-dithietanes, prepared from adamantane-2-thiones, failed to give the corresponding dithiiranes by treatment with 2KHSO5·KHSO4·K2SO4 or NaOCl-NaClO4. The dithiirane 3 thermally isomerized to 2,2,4,4-tetramethyl-1,5-diphenyl-8-oxa-6,7-dithiabicyclo[3.2.1 ]octane probably via 2,2,4,4-tetramethyl-1,5-diphenyl-5-thioxo-1-pentanone S-sulfide.
Stereochemistry of dithiirane 1-xxides: Optical resolution, absolute configuration, and racemization and isomerization of dithiirane 1-oxides
Ishii, Akihiko,Nakamura, Shin-Ya,Yamada, Tsuyoshi,Nakayama, Juzo
, p. 12203 - 12214 (2007/10/03)
Optical resolution of (1RS, 3SR)-(1) and (1RS, 3RS)-(2) dithiirane 1-oxides was achieved by HPLC equipped with a chiral column to give 1a and 1b and 2a and 2b, respectively. X-ray analyses proved absolute configurations of in and 1b to be (1R, 3S) and (1S, 3R), while those of 2a and 2b were determined to be (1R, 3R) and(1S, 3S), respectively, since 2a and 2b isomerized stereospecifically to 1b and 1a, respectively. Enantiomeric dithiirane 1-oxides la and 1b racemized to each other whereas 2a and 2b did not. To the racemization (oxygen migration) is proposed a mechanism involving homolysis of the S(O)-S bond at the initial step followed by a ring closure giving a 1,2,4-oxathietane intermediate. Isomerization between 1 and 2 was inhibited by a radical scavenger, DPPH.
Formation and Reactions of Novel Heterocycles: 1,3,4-Oxadithiolane, 1,3,4-Oxadiselenolane, 1,3-Oxathietane,and 1,3-Oxaselenetane Derivatives
Ding, Meng-Xin,Ishii, Akihiko,Nakayawa, Juzo,Hoshino, Masamatsu
, p. 1714 - 1721 (2007/10/02)
The reactions of 2,2,4,4-tetramethyl-1,5-diphenyl-1,5-pentanedione monohydrazone with S2Cl2 and Se2Cl2 gave 2,2,4,4-tetramethyl-1,5-diphenyl-8-oxa-6,7-dithiabicyclooctane (9) and 2,2,4,4-tetramethyl-1,5-diphenyl-8-oxa-6,7-diselenabicycloocta
Sulfurization of Nonenolizable Diketones
Ishii, Akihiko,Nakayama, Juzo,Ding, Meng-xin,Kotaka, Noboru,Hoshino, Masamatsu
, p. 2421 - 2427 (2007/10/02)
Sulfurization of nonenolizable diketones 1a-d by Lawesson's reagent (LR) and boron trisulfide reagent (B2S3) was investigated.Sulfurization of 1,4-diketone 1a with LR at 50 deg C in benzene affords disulfide 2 (23percent) and 1,3-dithietane 4a (70percent)
Stereoselectivity in the Hydride Reduction of Acyclic Diketones (1,2-, 1,3-, 1,4-, and 1,5-Induction)
Maier, Guenther,Roth, Cornelia,Schmitt, Reinhart K.
, p. 704 - 721 (2007/10/02)
Diketones 2, 5, 9, and 19 as well as hemiketal 22 react with lithium aluminum hydride to give mixtures of d,l- and meso-diols.The stereochemical assignment of the diols can be obtained either by direct comparison with authentic samples (1,2-diols) or by NMR differentiation of diastereotopic groups (1,3- and 1,5-diols) or by stereospecific cyclization to the sila-heterocycles 12 and 13 (1,4-diols).The 1,2- and 1,4-diketones preferably produce meso-diols, whereas 1,3- and 1,5-diketones mostly lead to d,l-isomers.These alternating stereoselectivities can be explained by a stepwise reduction generating complexes of types 24 - 27 which are attacked by excess hydride via a diastereoface differentiating mode.
