Simultaneous electron transfer from free and intercalated 4-benzoylpyridinium cations in cucurbit[7]uril.
نویسندگان
چکیده
N-Substituted 4-benzoylpyridinium monocations form stable host-guest complexes with cucurbit[7]uril (CB[7]) in DMSO (K(eq) approximately 0.6-1.9 x 10(3) M(-1)). Observation of simultaneous reversible and quasi-reversible e-transfer processes from the free and intercalated quests, respectively, is attributed to the pre-e-transfer host-guest equilibrium. The standard rate constant for Me-BP@CB[7] (k(s) = 1.0 x 10(-4) cm.s(-1)) reflects e-transfer across 5.7 A, corresponding to the distance of the intercalated guest from the outmost perimeter of CB[7] (5.3 A).
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ورودعنوان ژورنال:
- Organic letters
دوره 11 7 شماره
صفحات -
تاریخ انتشار 2009