Fluoroketones from

POLYMERS DERIVED FROM FLUOROKETONES. II. WETTING PROPERTIES OF FLUOROALKYL ACRYLATES AND METHACRYLATES. 

Nitrosyl fluoride reacts with steroidal olefins to give, ultimately, a-fluo-roketones [131], with steroidal vinyl lluorides, the reaction provides a,a di fluoroketones from intermediate nitroimines [197] (equation 34)... 

This topic has been reviewed [2, pp 94, 100-111, 130-134] All of the standard approaches to the synthesis of a compound like methyl 2-fluorostearate from methyl 2-bromostearate result mall yield of the 2-fluoro ester and the unsaturated esters. Although silver fluoride is not a new reagent, its use moist in wet acetonitrile to convert methyl 2-bromostearate to its fluoro ester is a departure from the traditional set of anhydrous conditions (Procedure 6, p 194) [71] In contrast, silver tetrafluoroborate converts a-chloroketones to their respective fluoroketones under anhydrous conditions. The displacement of less activated halogen groups by silver tetrafluoroborate to form their respective fluorides is novel Although silver tetrafluoroborate could not be used to convert an aliphatic terminal dichloromethyl or trichloromethyl group to its corresponding fluoro derivative, it is an effective fluorine source in other situations [72] (Table 8)... 

Zinc metalloproteases can be inhibited by fluoroketones. This inhibition should stem from complexation of the monoanion of the fluoroketone hydrate with zinc. Thus, S-amido and peptidyl fluoroketones inhibit carboxypeptidase and microbial... 

Asymmetric fluorination of the lithium enolate derived from tetralone 307 has been achieved with several new chiral A-fluoro-l,2-benzothiazine reagents (Scheme 44) <2000JOC7583, 2000CPB1954, see also 1999JFC(97)65>. For instance, sulfonamides 149 and 150 afford the opposite enantiomers of fluoroketone 308 in up to 79% yield and 62-70% ee. 

The enol acetates from acetophenone, benzylphenyl ketone, isopropylphenyl ketone, benzylmethyl ketone, and tetralone gave the corresponding a-fluoroketones, in a similar fashion. 

In the case of electrophilic substrates, the peroxometallic adduct results from the bimolecular 1,3-dipolar cycloaddition of the peroxo moiety to a cyanoalkene (equation 43)143 188 or a fluoroketone (equation 44).138... 

Nonactivated C—H bonds in imines can be selectively monofluorinated in HF-SbF5 in the presence of CC14 to yield the corresponding fluoroketones when the reaction mixture is quenched with HF-pyridine534 (Scheme 5.54). The transformation is initiated by hydride abstraction with CC13+ from the most reactive carbon farthest from the functional group and involves dicationic intermediates 134 and 135. 

Fig. 26 The elimination of HF from the 0-fluoroketone [68] is catalysed by antibody 1D4, elicited to hapten [70], to form the disfavoured (Z)-olefin [71]. This contrasts with the spontaneous process in which an anti-elimination reaction yields the ( )-<, 0-unsaturated ketone [69], The syn-eclipsed conformation of [70] is shaded.

Pentafluorophenyl thioketones are available [115] from the reaction of the corresponding fluoroketones with B2S3 formed in situ. Oxidation with monoperphthalic acid generated the sulfine, the X-ray structure of which revealed a dimer in the crystal lattice. 

Also, a-fluoroketones were prepared from a-acetoxystyrene and l-acetoxy-3,4-dihy-dronaphthalene [39,40] ... 

The synthesis of the fluoroketone that combines the retroamide type bond (76) is shown in Scheme 5. The 2,2-difluoro-3-hydroxyester 11 from a Reformatsky reaction was converted to the primary amide 12 by treatment with ammonia in diethyl ether. Reduction of the amide with borane dimethyl sulfide and protection of the resulting amine gave the protected intermediate 13. For the preparation of peptides XIV and XV, the hydroxy function was oxidized to the corresponding ketone using pyridinium dichromate. 

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