Fluoromethylated malonates

Table 11. Multinudear Spectral Data for Fluoromethylated Malonates [72]and Fluoromethylated Trimethylsilanes [97]...

Mono- and difluoromethylation involving the halogenofluoromethanes can be performed on malonic esters. A Curtius reaction, further performed on only one of the ester functions, leads to a-fluoromethyl amino acid (Figure 5.26). °... 

Multinuclear NMR data for homologous senes of fluoromethylated malo-nates [72] and trimethylsilanes [97] are compiled in Table 11. In both senes, fluoromethyl attachment is to a quaternary site These compounds are readily synthesized using fluorohalomethanes to incorporate the final fluoromethyl moiety All the malonates, except diethyl methyltnfluoromethylmalonate (4) [93], are isopropyl-substituted diethyl esters [72]. The silane data, with the exception of trimethyltrifluoromethylsilane (5) [95], are from reference 97 Chemical shift data are very comparable, with the malonates having higher proton and fluorine chemical shifts but slightly lower carbon values. The magnitudes of cf and 2J jp coupling are similar for both sets of compounds. 

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