Role of the Solvent in the Reactivity of Bis-4-imidazoline-2-selone Derivatives toward I2: An Experimental and Theoretical Approach

The reactivity of 1,1 '-bis(3-methyl-4-imidazolin-2-selone)methane (L1) and 1,2-bis(3-methyl-4-imidazolin-2-selone)ethane (L2) toward I2 has been explored in MeCN under different experimental conditions and compared with that in CH2Cl2. The compounds [L1 '](I)2 (I), [L1I]n(I)n (II), [L1(mu-Se)](I)2 center dot 1/2H2O (III), [L1I](I3)center dot 2I2 (IV), and [L2](I)2 center dot MeCN (V) were obtained and characterized. X-ray diffraction analyses point out an ionic nature for these compounds, which is presumably favored by the polarity of the solvent used. In particular, [L1I]n(I)n (II) represents the first example of an iodonium complex of imidazoline-2-selone derivatives, while [L1(mu-Se)](I)2 center dot 1/2H2O (III) represents a unique example of a dicationic [RSeSeSeR] triselane. Density functional theory calculations have allowed us to better understand the nature of the obtained compounds and to justify their formations in polarizing reaction conditions rather than in low polar solvents.