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The syntheses of haloacetates of iron(II) and their reactivity are described. The compound Fe(CF3COO)2, 1, crystallizes from CF3COOH/(CF3CO)2O solution as the polynuclear [Fe(CF3COO)2(CF3COOH)2]n, 2, which contains bridging trifluoroacetates and monodentate trifluoroacetic acid groups. Fe(CF3COO)2(DMF)x, as obtained from Fe(CO)5 and CF3COOH/(CF3CO)2O in DMF, reacts with dioxygen at room temperature to give two μ3-oxo compounds, namely, [Fe3(μ3-O)(CF3COO)6(DMF)3], 3, a Fe(II)-Fe(III)-Fe(III) derivative, and [Fe4(μ3-O)2(μ2-CF3COO)6(CF3COO)2(DMF)4], 4, containing Fe(III) atoms only, which have been characterized by X-ray diffraction methods. lron(II) chloro- and bromoacetates can be isolated by exchange reactions of iron(II) acetate with chloro- and bromo-substituted acetic acids in moderate to good yields. The stability of iron(ll) haloacetates decreases on increasing the atomic weight and the number of halogens on the α-carbon atom. The species Fe(CX3COO)2 (X = Cl, 7; Br, 8), in THF solution, slowly convert into [Fe3(μ3-O)(CCl3COO)6(THF)3], 11, or [Fe3(μ3-O)(CBr3COO)6(THF)3][FeBr4], 10, respectively. Likewise, when iron(II) acetate (or trifluoroacetate) is left for several hours in the presence of a variety of haloacetic acids in THF, selective formation of different species, depending on the nature of the starting compound and of the acid employed, is observed. The formation of these products is the result of C-X bond activation (X = Cl, Br) and haloacetato decomposition, which occurs with concomitant oxidation at the metal centers. Carboxylic acid degradation species (CH2XCOOH, CX4, CX3H, CX2H2, X = Cl, Br) have been observed by GC·MS. [ABSTRACT FROM AUTHOR]

The composition of 21 essential-oil samples isolated from Helichrysum italicum collected in seven locations of Elba Island (Tuscany, Italy), characterized by different soil types, during three different periods (January, May, and October 2010) was determined by GC-FID and GC/EI-MS analyses. In total, 115 components were identified, representing 96.8-99.8% of the oil composition. The oils were characterized by a high content of oxygenated monoterpenes (38.6-62.7%), while monoterpene and sesquiterpene hydrocarbons accounted for 2.3-41.9 and 5.1-20.1% of the identified constituents, respectively. The main oxygenated derivatives were nerol (2.8-12.8%) and its ester derivative neryl acetate (5.6-45.9%). To compare the chemical variability of the species within Elba Island and between the island and other localities within the Mediterranean area, studied previously, multivariate statistical analysis was performed. The results obtained showed a difference in the composition of the essential oils of H. italicum from Elba Island, mainly due to the environment where the plant grows, and, in particular, to the soil type. These hypotheses were further confirmed by the comparison of these oils with essential oils obtained from H. italicum collected on other islands of the Tuscan archipelago., (Copyright © 2013 Verlag Helvetica Chimica Acta AG, Zürich.)