Fluorinated acetone structure

Key Words Ethylene oxide, Propylene oxide. Epoxybutene, Market, Isoamylene oxide. Cyclohexene oxide. Styrene oxide, Norbornene oxide. Epichlorohydrin, Epoxy resins, Carbamazepine, Terpenes, Limonene, a-Pinene, Fatty acid epoxides, Allyl epoxides, Sharpless epoxidation. Turnover frequency, Space time yield. Hydrogen peroxide, Polyoxometallates, Phase-transfer reagents, Methyltrioxorhenium (MTO), Fluorinated acetone, Alkylmetaborate esters. Alumina, Iminium salts, Porphyrins, Jacobsen-Katsuki oxidation, Salen, Peroxoacetic acid, P450 BM-3, Escherichia coli, lodosylbenzene, Oxometallacycle, DFT, Lewis acid mechanism, Metalladioxolane, Mimoun complex, Sheldon complex, Michaelis-Menten, Schiff bases. Redox mechanism. Oxygen-rebound mechanism, Spiro structure. 2008 Elsevier B.V. 

FIGURE 1.22 Structures of peroxycarboxylic acid (1), fluorinated acetone (2), dimethyldioxirane (DMD) (3), and their respective transition states (4-6). 

Figure 5 (a)-(c) shows the absorption spectra of some halogenated ketones in the near ultraviolet. In the case of acetone itself the absorption may be attributed to an n - tt transition associated with the carbonyl group. The substitution of halogen atoms leads to an increase in the molecular extinction coefficient and a shift of the absorption maximum toward the red. The ketones containing both chlorine and fluorine atoms show absorption curves with some fine structure but it is not possible to find any correlation between the structure and the shape of the absorption curve. 

Fifolt [ 130] reported this chemical shift additivity method for fluorobenzenes in two deuterated solvents d6 acetone and d6 dimethyl sulfoxide (DMSO) Close correlations between experimental and calculated fluorine chemical shifts were seen for 50 compounds Data presented in Table 18 result from measurements in deuterochloroform as (he solvent [56] Fluorine chemical shifts calculated by this additivity method can be used to predict approximate values for any substituted benzene with one or more fluorines and any combination of the substituents, to differentiate structural isomers of multisubstituted fluorobenzenes [fluoromtrotoluenes (6, 7, and 8) in example 1, Table 19], and to assign chemical shifts of multiple fluorines in the same compound [2,5 difluoroamline (9) in example 2, Table 19] Calculated chemical shifts can be in error by more than 5 ppm (upfield) in some highly fluonnated systems, especially when one fluonne is ortho to two other fluorines Still, the calculated values can be informative even in these cases [2,3,4,6-tetrafluorobromobenzene (10) in example 3, Table 19]... 

Many carbonyl addition and substitution reactions are carried out under acidic conditions or in the presence of Lewis acids. Qualitatively, protonation or complexation increases the electrophilicity of the carbonyl group. The structural effects of protonation have been examined for formaldehyde, acetaldehyde, acetone, formamide, and formyl fluoride. These effects should correspond to those in more complex carbonyl compounds. Protonation results in a substantial lengthening of the C=0 bond. The calculated [B3LYP/ 6-31-H-G(phase proton affinities reflect the trend of increasing basicity with donor groups (CH3, NH2) and decreased basicity for fluorine. 

Viehe and his co-workers86 carried out the addition of chloroform to carbonyl groups in liquid ammonia the yield depended on the structure of the acceptor their condensing agents were sodamide, sodium hydroxide, and sodium alkoxides acetone, ethyl methyl ketone, diethyl ketone, cyclo-pentanone, cyclohexanone, and benzaldehyde were treated in this way. It is also possible to add tribromomethane, but not fluorinated methanes. 

The same fluorinated mercuracycle links thiocyanate anions (in acetone solution) and the tetra-n-butylammonium salt of [(n-C6F4Hg)3SCN] has been isolated and structurally characterized [6]. The crystal structure contains a helical chain of alternating (o-C6F4FIg)3 molecules and SCN ions. The stacks are held by sulfur atoms at Hg- -S distances in the range 3.06-3.36 A, with one longer at 3.87 A. Thus, both host-guest complexation and supramolecular self-assembly if observed with these compounds. 

---