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Direct <sup>18</sup>F-Labeling of Biomolecules via Spontaneous Site-Specific Nucleophilic Substitution by F<sup>–</sup> on Phosphonate Prostheses
作者:Chao Wang、Lei Zhang、Zhaobiao Mou、Wanru Feng、Zhongjing Li、Hongzhang Yang、Xueyuan Chen、Shengji Lv、Zijing Li
DOI:10.1021/acs.orglett.1c01211
日期:2021.6.4
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Shi, Min; Yamamoto, Kiichi; Okamoto, Yoshiki, Phosphorus, Sulfur and Silicon and the Related Elements, 1991, vol. 60, # 1.2, p. 1 - 14
作者:Shi, Min、Yamamoto, Kiichi、Okamoto, Yoshiki、Takamuku, Setsuo
DOI:——
日期:——
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Nonlinear Broensted Relationships in the Reactions of Phenoxide Ions with Bis(4-nitrophenyl) Phenylphosphonate in H2O-Me2SO Mixtures. Solvation Effects
作者:Francois Terrier、Gilles Moutiers、Lan Xiao、Eric Le Guevel、Frederic Guir
DOI:10.1021/jo00111a037
日期:1995.3
The second-order rate constants (k(ArO)) for reaction of substituted phenoxide ions with bis(4-nitrophenyl) phenylphosphonate in aqueous as well as various aqueous dimethyl sulfoxide (Me(2)-SO) mixtures are reported. Traditional Bronsted plots of log k(ArO) vs pK(a)(ArOH) are linear at low pK(a)(ArOH) but show very strong downward curvature at high pK(a)(ArOH). In each solvent, the break point in the Bronsted plot occurs at a pK(a)(ArOH) value which is much higher than that corresponding to the basicity of the leaving p-nitrophenoxide ion, suggesting that the observed levelling off does not reflect a change in the identity of the rate-determining step in a two-step process involving formation of a pentacoordinate intermediate. An analysis of the data on the basis of a novel strategy recently designed by Buncel and co-workers for the construction of Bronsted plots in solvent mixtures confirms this conclusion. It is proposed that the curvature in the traditional Bronsted plots is the reflection of strong imbalances in the transition states of the reactions, and it is suggested that these imbalances are essentially of solvational nature.
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DHAWAN, BALRAM;REDMORE, DEREK, J. CHEM. RES. (S),(1990) N, C. 184-185
作者:DHAWAN, BALRAM、REDMORE, DEREK
DOI:——
日期:——
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SHI, MIN;YAMAMOTO, KIICHI;OKAMOTO, YOSHIKI;TAKAMUKU, SETSUO, PHOSPH., SULFUR AND SILICON AND RELAT. ELEM., 60,(1991) N-2, C. 1-14
作者:SHI, MIN、YAMAMOTO, KIICHI、OKAMOTO, YOSHIKI、TAKAMUKU, SETSUO
DOI:——
日期:——