1
1
2 N. Shaham, H. Cohen, R. van Eldik and D. Meyerstein, J. Chem. Soc.,
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45 Since radical and nucleophilic additions to benzenediazonium ion
normally take place at N
b
or conjugated ring positions, we discount
•
1
1
1
4 M. L. Crossley, R. H. Kienle and C. H. Benbrook, J. Am. Chem. Soc.,
ipso-attack on 1 either by An or by a nucleophilic organocopper
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be Ullmann reaction in which aryl halides are coupled to give biaryls
on reaction with copper metal at high temperature. Organocopper
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Soc., 1976, 98, 748, but we consider it implausible that a diazonium
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relevance of Ullmann-type reaction to the formation of the symmetrical
1
940, 62, 1400.
5 The method of G. J. Kubas, Inorg. Synth., 1990, 28, 68 for the
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6 C. Diaz, J.-P. Gisselbrecht, M. Gross, J. Suffert and R. Zeissel,
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1
1
1
7 W.-Y. Ng, J. Chem. Educ., 1988, 65, 727.
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ꢀ
4,4 -dimethoxybiphenyl, 4, here.
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2
2
2
0 (a) P. Hemmerich and C. Sigwart, Experientia, 1963, 19, 488; (b) A.
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2 Reduction potentials of 0.34 V and 0.41 V have been quoted for the
complexes having n = 1 and 2, respectively: N. Navon, A. Burg, H.
Cohen, R. van Eldik and D. Meyerstein, Eur. J. Inorg. Chem., 2002,
47 (a) Although aryl radicals are known to be highly reactive towards
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2
8019; (b) X. Fang, R. Martens and C. von Sonntag, J. Chem. Soc.,
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were scarcely affected by its exclusion.
48 D. F. Shriver, P. W. Atkins and C. H. Langford, in Inorganic Chemistry,
Oxford University Press, Oxford, 1991, p. 211.
4
23.
49 Simula: a kinetic simulation programme adapted from prior software
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2
2
3 P. Hanson, S. C. Rowell, A. B. Taylor, P. H. Walton and A. W. Timms,
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1
b) J. Barbosa, R. Berg e´ s, V. Sanz-Nebot and I. Toro, Anal. Chim. Acta,
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5
1
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2
2
5 A. D’Aprano and R. M. Fuoss, J. Phys. Chem., 1969, 73, 400.
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2
2
2
7 If individual buffer ratios, as opposed to their mean, are used for
corrections to I50 in Table 4, the value of z
i
z
j
obtained, −(2.27 ± 0.20),
is not significantly different.
8 The quasi-third order rate constant l3(50) approximates the true third
3
6
−2 −1
order constant k3(50) = (1.81 ± 0.13) × 10 dm mol
iv).
s , see Results
(
23
9 We have previously described the gas-displacement cell used which is
an adaptation of one reported in the literature: M. L. Crossley, R. H.
Kienle and C. H. Benbrook, Ind. Eng. Chem., Anal. Ed., 1940, 12, 216.
0 See ref. 13b, pp. 222–225.
3
3
3
1 A. H. Lewin and T. Cohen, J. Org. Chem., 1967, 32, 3844.
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3
59 D. Griller, D. Schmid and K. U. Ingold, Can. J. Chem., 1979, 57,
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2
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(
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62 An EPR spectrum originallyassigned to PhN
•
Koike and A. Rieker, Bull. Chem. Soc. Jpn., 1986, 59, 1877.
2
(W. T. Dixon and
3
3
3
5 M. N. Weaver, S. Z. Janicki and P. A. Petillo, J. Org. Chem., 2001, 66,
R. O. C. Norman, J. Chem. Soc., 1964, 4857) was subsequently
+
•
1
138.
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3
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4
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4
4
2 R. W. Alder, R. Baker and J. M. Brown, in Mechanism in Organic
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3 We write formulae of complexes with established coordination con-
ventionally with square brackets [] but use () and {} for postulated
complexes where the full coordination is uncertain.
6
98 | Org. Biomol. Chem., 2007, 5, 679–698
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