Enforcement blockades

N (5) is a very weak basic site in FloX (pK < 0), a moderately strong one in FI" (pK 8.5) and again very weak in Flred. In both HFl red (pK 6.5) and FIoX (pK 0.5), N(l) is the preferred protonation site. This explains why enforced blockade of the N(5)-lone pair favors the radical, i.e., le"-transfer, while enforced N( 1)-blockade favors Flox and Flred and, therefore, 2e"-transfer. If, however, the blockade is achieved by metal instead of protons, the attachment site at Flox is switched from N (1) towards N (5) because of the 4 ,5-bidentate mode of metal fixation. Hence, metal complexation as such is sufficient to shift the 2e -transfer system into a le"-transfer system. For redox-active metal,... 

The rules of the Paris Declaration (1856) and the London Declaration (1909) on naval blockades have more or less survived, although the modem weapons technology has made the establishment and enforcement of a close blockade virtually impossible. Military manuals and contemporary State practice provide ample proof of the continuing validity of the traditional mles. ... 

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