Fluoroacyl derivative

For most cases, common fluoroacyl derivatives are sufficiently reactive and selective Thus conversion of perfluoroglutaric dichloride to a monomethyl ester by methanol proceeds smoothly under the appropriate reaction conditions [17] (equation 9) Perfluorosuccinic acid monoester fluoride, on the other hand, is prepared most conveniently from perfluorobutyrolacetone (equation 10) Owing to the strong acidity of a fluorinated carboxylic acids, Fischer esten-ficaiton with most aliphatic alcohols proceeds autocatalytically [79 20]... 

In a similar vein, the addition of XeF2 to [Ir(CO)3(PR3) 2]+ results in addition of F2 across an Ir—C bond to give the fluoroacyl derivative,... 

Rate constants and activation parameters for the carbonyl migration reactions of fluoroacyl derivatives (13) to give six-co-ordinate fluoroalkyl complexes (14) are given in Table 2. The rates decrease in the order CFH2>CF3>CF2H, which does not... 

F]Fluoroacylation with [18F]fluoroacetic acid and [2-18F]fluoropropionic acid derivatives... 

Semicarbazide and its derivatives including thiosemicarbazide react with 2-poly-fluoroacyl-cyclohexanones, giving exclusively hydroxy-pyrazolines (99IZV361) (Scheme 107). The choice between the two isomeric possible forms, F and X, was made based on an X-ray investigation (for the derivative with the -C6F13 substituent). 

V-Fluoroacyl-imidazoles react readily with hydroxyl groups and secondary or tertiary amines to form acyl derivatives. No acids are produced which could hydrolyse the products. The imidazole produced as a by-product is relatively inert. A reaction using JV-trifluoroacetylimidazole is shown below ... 

Making a formyl derivative adds only 28 to the molecular weight of a compound, and for this reason has found particular favour in situations where several groups have to be blocked, such as in steroid chemistry, where the formyl derivatives appeared to be among the most suitable for the analysis of steroids by gas chromatography. However, it must be said that formyl derivatives are not necessarily the most volatile some of the per-fluoroacyl or methoxycarbonyl derivatives may be more volatile than the corresponding formyl ones. 

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