Replacement of Cl by

The most practicable and versatile laboratory and industrial route to polyfluoroaromatic compounds involves the use of potassium fluoride in nucleophilic displacement of 

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H3P04 (Ka = 7.1 xlCT3), and it is. The only difference between CCl3CH2COOH and CCl2FCH2COOH is the replacement of Cl by F. Since F is more electronegative than Cl, CCl3CH2COOH should be a weaker acid than CCl2FCH2COOH. ... 

Vaska118 found a shift of v(CO) in trans- but not cis-X—M—CO arrangements of about 20-30 cm-1 to higher frequency when X = D. He ascribed this result to coupling effects. Halpern119 showed that kH/k0 for the replacement of Cl- by pyridine in frans-PtHClLj is 1.44, unexpectedly large for a secondary isotope effect. He ascribed this to Pt—H bond weakening in the transition state. 

Replacement of Cl by pyridine, or one of its derivatives, lead to an enhancement of emission properties of rhenium(I) complexes as noted by entries in Table 1. 

Cb) Replacement of Cl by the isopcntyl group does not change the priorities of the groups on the chiral C. There is one optically active product, whose two chiral C s have R configurations. 

More detailed studies showed that what is supposed to be the actual catalyst is formed from the RhCl3 precatalyst by replacement of Cl by ethoxy (from... 

No direct evidence for Mn(V) or peroxide-like intermediates have been observed yet in any native S, state. However, release of hydrogen peroxide occurs in a modified S2 state formed under a variety of conditions (removal of Cl , replacement of Cl by F and solubilization with lauryl choline chloride)(reviewed in ). These results show that the driving force for HO-OH bond formation already exists at the modified S2 oxidation level. 

Lines c and d depict the corresponding changes with successive replacements of CL by NH3. In this case, the downward slope of the fragment orbitals is due to increasing... 

The interaction of amino acids with Mo Clg" has been surveyed and in all cases replacement of Cl by amino acid is evidenced and the relative ease of this reaction in many instances is a reflection of the affinity of the M02 core for carboxylate groups. The complex with glycine M02(O2CCH2NH3)4(SOj2 4H2O was isolated and its crystal structure determined. The preparation of a heteronuclear quadruple metal— metal bond has been achieved in the formation of [CrMo(02CMe)J in which the Cr—Mo bond length is 205.0(1) pm. The heteronuclear metal—metal bond is much more labile than related homonuclear bonds and is readily cleaved under mild conditions. ... 

The chlorine atoms are reactive, and most reactions of chlorophosphazenes involve replacement of Cl by groups such as alkyl, aryl, OH, OR, NCS, or NR2. Alkyl or aryl groups may be introduced using lithium or grignard reagents. 

Figure 4. pHCl over H/Na/Cl/C104 and H/Na/Cl/S04 aqueous solutions of constant stoichiometric ionic strength 5.0 mol kg", showing effect of progressive replacement of Cl" by C104", and S04 ". In both systems total mH is equal to 1.5 mol kg. Symbols -measurements lines - calculated values. Inset calculated free ion concentration in the solutions containing S04 . 

In the environmental compartments, PCBs are degraded mainly hy microorganisms. Mono-, di-, and trichlorobiphenyls are broken down relatively quickly, whereas the more highly chlorinated PCBs are much more persistent. Highly chlorinated PCBs are reductively dechlorinated anaerobically with replacement of Cl by H, and the less-chlorinated products are subject to aerobic breakdown processes. The formation of ortho-dioh is thought to involve arene epoxides (Figure 11). 

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