- 著者
- Munetaka KUNISHIMA Shohei TANI
- 出版者
- The Society of Synthetic Organic Chemistry, Japan
- 雑誌
- Journal of Synthetic Organic Chemistry, Japan (ISSN:00379980)
- 巻号頁・発行日
- vol.57, no.2, pp.127-135, 1999-02-01 (Released:2009-11-16)
- 参考文献数
- 31
- 被引用文献数
- 7 7
Reduction of aryl and vinyl radicals to the corresponding organosamarium species by SmI2 can be attained by using benzene-HMPA as a solvent system. Thus, SmI2-mediated Barbier- and Grignardtype coupling reactions between ketones and aryl, vinyl, or alkynyl iodides proceed via organosamarium species in benzene-HMPA. Reductive dehalogenation of 1, 1-dihaloalkenes by SmI2 in benzene-HMPA generates alkylidenecarbenes, which undergo either 1, 5-C-H insertion giving cyclopentenes or 1, 2-shift giving alkynes. On the other hand, SmI2 was found to be useful to effect 2, 3-rearrangement under mild conditions. Metalated ethers undergoing Wittig rearrangement are regioselectively generated by either an intramolecular 1, 5-hydrogen transfer of a vinyl radical, generated by a single electron transfer from SmI2 to γ-haloallyl ethers, or a net two-electron reduction of diallyl acetals with the liberation of an allyloxy samarium by SmI2 in acetonitrile. 2, 3-Rearrangement of allylic sulfonium ylides can be effected by the reaction of allylic sulfides with samarium carbenoid, generated from CH2I2 and SmI2 in THF.
- 著者
- Shigehiro Yamaguchi Aiko Fukazawa Masayasu Taki
- 出版者
- The Society of Synthetic Organic Chemistry, Japan
- 雑誌
- Journal of Synthetic Organic Chemistry, Japan (ISSN:00379980)
- 巻号頁・発行日
- vol.75, no.11, pp.1179-1187, 2017-11-01 (Released:2017-11-09)
- 参考文献数
- 94
- 被引用文献数
- 14
Phosphole P-oxide is a useful building block for π-conjugated materials due to its nonaromatic and electron-accepting character. We have synthesized a series of ring-fused derivatives of phosphole P-oxide based on the intramolecular nucleophilic cyclization of appropriate alkyne precursors or radical phosphanylations. Some of the thus obtained compounds exhibited intriguing fluorescence properties and were applied to fluorescence imaging. A donor-acceptor-type benzo[b]phosphole P-oxide with a (diphenylamino)phenyl group exhibited large solvatochromism in its fluorescence spectra, and could hence be used as a staining agent for lipid droplets. C-Naphox and PB430, which consist of fully ring-fused π-conjugated ladder-type scaffolds, exhibited outstanding photostability and their absorption and emission properties were suitable for super-resolution STED imaging. Moreover, using PB430-conjugated antibodies, we carried out a 3-D reconstruction of the STED images and developed a photostability-based multicolor STED imaging technique.
- 著者
- Kazuhiko Semba Yoshiaki Nakao
- 出版者
- The Society of Synthetic Organic Chemistry, Japan
- 雑誌
- Journal of Synthetic Organic Chemistry, Japan (ISSN:00379980)
- 巻号頁・発行日
- vol.75, no.11, pp.1133-1140, 2017-11-01 (Released:2017-11-09)
- 参考文献数
- 154
- 被引用文献数
- 4
Cross-coupling reactions based on catalytically generated organocopper species have been developed by cooperative Pd/Cu or Ni/Cu catalysis. Alkyl or alkenylcopper intermediates generated via the hydrocupration or borylcupration of alkenes or alkynes engage in Pd- or Ni-catalyzed reactions with organic electrophiles. These reactions circumvent the laborious pre-synthesis and isolation processes of organometallics that characterize conventional cross-coupling reactions, and they are hence more step-economical. Moreover, highly functionalized organocopper species, which are difficult to access using conventional methods, can be obtained from readily available alkenes and alkynes. Thus, cross-coupling reactions by cooperative Pd/Cu or Ni/Cu catalysis represent powerful tools for the construction of complex structures from readily available starting materials in a single operation.