Adducts charge transfers

Charge-transfer adducts are formed with the gold(I) trimers [Au3(MeN=COR)3] (R = Me, Et), which act as electron donors, and organic electron acceptors as nitro-9-fluorenes. The structures of these adducts involve mixed stacks in which the gold trimers and the planar nitro-fluorenes are interleaved.3130 No luminescence has been observed from these solid charge-transfer adducts, which is not surprising since the luminescence of [Au3(MeN=COR)3] is a property that is associated with the supramolecular organization in the solid. 

With bromine, diorganosulfldes tend to furnish charge transfer adducts, whereas selenides can give equilibria between C.T. adducts and products from oxidative addition, i.e. molecular Se(IV) compounds.23 A particular example of such equilibria is the bromination of selenanthrene reported by Nakanishi et al.24 (see Chapters 8.2 and 10.3).24... 

It should be pointed out that the treatment of phosphorus or sulfur donors bearing ferrocenyl groups with diiodine results in the formation of molecular charge-transfer adducts without simultaneous oxidation of the ferrocenyl groups (Durfey et al. 2000, Gridunova et al. 1982). At the same time, the reaction of 4-ferrocenyl-l,3-dithiolene-2-thione with diiodine leads to a charge-transfer complex in which the iron has been oxidized from Fe" to Fe ". This was confirmed by magnetic measurements and Moessbauer spectroscopy (Allen et al. 2003). 

During studies on the interaction between sulfur donors and suitable acceptors, the solid-state structure of the charge-transfer adduct l,3-dithiane-2-thione- -diiodine 111 was investigated <1999IC4626> the CS3 moiety is planar, the I2 molecule lies in the same plane with the first iodine atom separated by 2.755 A and the I-I vector is practically co-linear with the S-I one. The I-I bond length is slightly elongated with respect to a free iodine molecule. 

Figure 13.22 The circumrotation of the tetracationic cyclophane component of catenane 254+ can be controlled reversibly by adding-protonating -hexylamine that forms a charge transfer adduct with the diazapyrenium unit of the catenane.

D=Electron-rich donor species Fallerides and charge-transfer adducts... 

Other studies have brought out the ambivalent characteristics of many porphyrins in charge-transfer adducts [189-192]. Porphyrin fluorescence quenching, a characteristic of complexation, occurs for a variety of aromatic donors and acceptors. The porphyrins are known [189-192] to form charge-transfer complexes with some amino acids and the indole tryptophan [193], some steroids [194], and some vitamins [194]. 

Ardiles, P., E. Trollund, M. Isaacs, F. Armijo, and M.J. Aguirre (2001). Evidence of a stable charge-transfer adduct between 2-mercaptoethanol and cobalt-poly-telra-aminophthalocyanine. y. Coord. Chem. 54(3-4), 183—191. 

The electrochemical reduction of backminsterfullerene constituting the anode in a cell containing Ph4PCl as supporting electrolyte gives rise to the formation of crystals of a charge-transfer adduct on the surface of the electrode ... 

Antoniadis, C.D., Hadjikakou, S.K., HadjUiadis, N. et al. (2006) Synthesis and structures of Se analogues of the antithyroid drug 6-n-propyl-2-thiouracil and its alkyl derivatives formation of dimeric Se—Se compounds and deselenation reactions of charge-transfer adducts of diiodine. Chem. Eur. J., 12, 6888-6897. 

Aragoni, M.C., Area, M., Devillanova, FA. et al. (1999) Charge-transfer adducts between donors containing chalcogens (S and Se) and diiodine solution studies. Coord. Chem. Rev., 184, 271-290. 

Photoexcitation (X = 313 nm) of the charge-transfer adducts of N with CuBr(Py)(PPh3) or Cu[HB(Pz)3] in hexane (Py = pyridine, Pz = 1-pyrazolyl) gives rise to Q with = 0.37-0.65. The photorearrangement of the complexes of N with halo(ferrocenyl-diphenylphosphine)copper(I) tetramers... 

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