Synthesis of β,β-difluoroacrylates

General Method for the Preparation of β,β-Difluoroacrylates Using BrF3

“…Compounds 6 possess coupling constant 2 J F,F of 0−1 Hz, and the coupling constant represent the 4 J F,H . This was reported early and we observed another small coupling constant (represented by - m), probably due to the other 4 J F,H or the small 2 J F,F constant.…”

“…Combining these two subjects is of potential interest for making precursors for compounds used in coating, polymerization, special optical properties, and more . However, the only known methods of preparing β,β-difluoroacrylates are the reactions of malonic esters with CF 2 Br 2 and reactions of Grignard reagents with 2-(trifluoromethyl)propenoic acid …”

Attaching the Fluorine Atom to Organic Molecules Using BrF3 and Other Reagents Directly Derived from F2

“…29 However, the known methods of preparing β,βdifluoroacrylates are limited. 30,31 We found that the difluoromethyl sulfones, 17, described in Scheme 7, can also serve as a good starting point for making these acrylic derivatives by treating them with Raney nickel, eliminating both the bromine atom and the sulfone group. Methyl 2-alkyl-β,β-difluoroacrylates (23) were eventually formed in 55-80% overall yield.…”

Stereocontrolled Synthesis of β-Difluoromethylated Materials

“…Furthermore, the highly geometrically controlled syntheses of trisubstituted alkenes with a fluoromethyl group are not known in the fields examining Hörner−Wadsworth−Emmons reactions and Wittig reactions. − In contrast, It is known that difluoromethylated materials have been prepared from terminal difluoroolefins by hydrogenation, using a 10% palladium on carbon catalyst or BrF 3 , and their reactions in radical addition, electrophilic cyclizations, and Claisen rearrangement, for the synthesis of difluoromethylene-containing compounds, have been reported. To date, synthetic strategies for the preparation of terminal difluoroolefins have been based on a few methods: (1) the lithiation of 1,1-difluoroethene and trapping of the intermediate with CO 2 , (2) the decarboxylation of bromodifluoromethylated malonate, (3) the dehydrofluorination of trifluorinated isobutyrate, and (4) the Wittig difluoromethylation of pyruvate . Moreover, the chemistry of terminal difluoroolefins, which do not undergo elimination to form fluoroolefins, has not been studied for the construction of regio- and stereocontrolled fluorinated materials, − except for indium-mediated allylation .…”