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이남호;Richard C. Larock
- Bulletin of the Korean Chemical Society
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- v.16 no.9
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- pp.859-863
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- 1995
The prostaglandin analogue 12-epi-PGF2α (2) has been synthesized from optically active cis-4-t-butyldimethylsilyloxy-2-cyclopenten-1-ol (4b) in 4 steps in an overall yield of 21%. An extremely efficient Pd(Ⅱ)-mediated, three-component coupling reaction is employed to obtain the key intermediate 9.
https://doi.org/10.5012/bkcs.1995.16.9.859 인용 PDF

Kim, Ji Dang;Pyo, Ayoung;Park, Kyungho;Kim, Gwui Cheol;Lee, Sunwoo;Choi, Hyun Chul
- Bulletin of the Korean Chemical Society
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- v.34 no.7
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- pp.2099-2104
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- 2013
We present here an efficient and simple method for preparation of highly active Pd heterogeneous catalyst (CNT-Pd), specifically by reaction of dichlorobis(triphenylphosphine)palladium ($Pd(PPh_3)_2Cl_2$) with thiolated carbon nanotubes (CNTs). The as-prepared CNT-Pd catalysts demonstrated an excellent catalytic activity for the carbon-carbon (C-C) cross-coupling reactions (i.e. Suzuki, Stille, and decarboxylative coupling reactions) under mild conditions. The CNT-Pd catalyst could easily be removed from the reaction mixture; additionally, in the decarboxylative coupling of iodobenzene and phenylpropiolic acid, it showed a six-times recyclability, with no loss of activity. Moreover, once its activity had decreased by repeated recycling, it could easily be reactivated by the addition of phosphine ligands. The remarkable recyclability of the decarboxylative coupling reaction is attributable to the high degree of dispersion of Pd catalysts in CNTs. Aggregation of the Pd catalysts is inhibited by their strong adhesion to the thiolated CNTs during the chemical reactions, thereby permitting their recycling.
https://doi.org/10.5012/bkcs.2013.34.7.2099 인용 PDF KSCI

Xu, Jun
- Bulletin of the Korean Chemical Society
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- v.34 no.11
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- pp.3265-3268
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- 2013
The multi-hydrogen bonded systems with the solvated electrons are investigated at the B3LYP/6-311++$G^{**}$ basis set level. The symmetrical linear geometrical characteristic is common for the dimer systems, while for the tetramer system, the tetrahedron configuration is generated. The NBO charge analyses demonstrate that the multi-hydrogen-multi-electron (mH-ne) coupling exist in these anion systems, as is supported by the electrostatic potential and the molecular orbital analyses. The positive chemical shift value of the central hydrogen ($H_c$) and the negative chemical shift value of the terminal hydrogen ($H_t$) indicate that the $H_c$ is electronegative while the $H_t$ is electropositive, respectively. Strong coupling between two central hydrogen atoms is demonstrated by the large spin-spin coupling constants. The solvated electron donates significant contributions for the stability of these systems.
https://doi.org/10.5012/bkcs.2013.34.11.3265 인용 PDF KSCI KPUBS HTML