Trifluoromethyl isocyanide

Trifluoromethyl isocyanide traps the bis(trifluoromethyI)nitroxyl radical at the terminal carbon atom with the formation of an intermediate radical that decomposes spontaneously to give trifluoromethyl isocyanate as the end product (Table 14).238... 

Hexafluoroacetone and trifluoromethyl isocyanide react in an unexpected way to provide a bicyclic five-membered ring system [87AG(E)92I] (Scheme 94). 

In order to prove this assumption, several trifluoromethyl isocyanide complexes with metals in low oxidation states have been synthesized, and their spectroscopic data, reactivity and structures have been studied. 

Dinuclear Trifluoromethyl Isocyanide Complexes and Cluster Compounds... 

Due to its strong K accepting ability, the trifluoromethyl isocyanide ligand tends to occupy the bridging position in dinuclear complexes and clusters even if the analogous carbonyl derivative has only terminal ligands as in [CpM(CO)3]2 (M = Mo, W) (27) or M3(CO)i2 (M = Ru, Os) (28 9). 

G. Simonneaux et al. (57) published the synthesis and complexation to ruthenium(II) and iron(in) m 5(9-tetraphenylporphyrins of two new fluorinated alkyl isocyanides, 2-monofluoroethyl isocyanide and 2,2,2-trifluoroethyl isocyanide. A new synthesis of trifluoromethyl isocyanide, pentafluoroethyl isocyanide and heptafluoropropyl isocyanide from R-N=Cp2 (R = CF3, C2F5, C3F7) using triphenyl phosphine has been reported (58). Geometries and HOMO and LUMO energies of fluorinated vinyl isocyanides have been calculated (59). Pentacarbonyl chromium complexes of both isomers of the first fluorinated diisocyanide, l,2-diisocyano-l,2,3,3,4,4-hexafluoro cyclobutane have been isolated from a [2+2] cycloaddition reaction of pentacarbonyl(trifluorovinyl isocyanide) chromium. The structure of the cis isomer has been elucidated by X-ray crystallography (60),... 

The trifluoromethyl isocyanide thus formed isomerizes to trifluoromethyl cyanide when heated, reacts with mercuric oxide to yield trifluoromethyl isocyanate, and must be stored at low temperatures otherwise it polymerizes to a yellow solid which possibly has the structure [-C( NCF3)C( NCFj)-]n- Reference has already been made to the preparation of oxazetidines from trifluoronitrosomethane and A AT-bistrifluoromethylamino-substituted allenes (see p. 100). Possibly of greater interest is the preparation in low yield of the flrst perhalogeno oxazetidines bearing no per- or poly-fluoroalkyl substituent on nitrogen (see Scheme 8). Reaction of perfluoro-l, 2-oxazetidine, r. 

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