1825-23-6Relevant articles and documents
Scherer,Kirby
, p. 7352 (1968)
Reactions of dimethoxycarbene with cyclic perchlorinated olefins and ketones
Dunn, James A.,Pezacki, John Paul,McGlinchey, Michael J.,Warkentin, John
, p. 4344 - 4352 (2007/10/03)
Reactions of dimethoxycarbene (2), a carbonyl group equivalent, with perchlorinated olefins and ketones were investigated. Thermolysis of 2,2- dimethoxy-5,5-dimethyl-Δ3-1,3,4-oxadiazoline (1) at 110 °C generated 2, which reacted with hexachlorocyclopentadiene (4), octachlorocycloheptatriene (12), octachlorobicyclo[3.2.0]hepta-3,6-diene (24), hexachlorotropone (28), hexachlorobicyclo[3. 2.0]-hepta-3,6-dien-2-one (32), and tetrachloro-1,4- benzoquinone (35). Reactions of 2 with perchlorinated olefins 4, 12, and 24 led to esters or, in the case of 12, to a ketene acetal. Their formation is rationalized in terms of Michael-like addition and displacement (S(N)2' or S(N)2', if concerted) of allylic chlorine atoms by 2, yielding ion pairs that either dechloromethylate to esters or dechlorinate to a ketene acetal. In contrast, the reactions of 2 with unsaturated perchloroketones 28, 32, and 35 led to ring contraction, ring expansion, and aromatization, respectively. The products from these reactions are consistent with nucleophilic addition of 2 at the carbonyl moiety rather than Michael-type addition. Dimethoxycarbene- d3 was used to show that demethylation in the latter reaction was intermolecular. Mechanisms for the different reaction courses are proposed.
Process for the preparation of halogenated benzoyl fluorides
-
, (2008/06/13)
A process for the preparation of a halogenated benzoyl fluoride, which comprises contacting a halogenated benzotrifluoride of the formula STR1 in which m and n independently of one another represent an integer from 0 to 5, the sum of m and n being 5, with at least one sulphur compound of the formula STR2 in which X denotes fluorine, chlorine or hydroxyl and Y represents hydroxyl, or X and Y together denote an oxygen atom linked to the sulphur atom by a double bond, at an elevated temperature, and after reaction with the halogenated benzotrifluoride, removing the sulphur compound from the reaction mixture in the form of a compound of the formula STR3 in which X has the meaning given and Hal represents fluorine or chlorine, the reaction product is further reacted with potassium fluoride at an elevated temperature and under increased pressure.
