Convenient preparation and functionalization of 2-metallated pentafluoropropenes

A Convenient Method for the Synthesis of Stable α‐Fluoro Enamines of Nucleobases

“…On treatment of PFP with LDA or tBuLi and subsequently with ZnCl 2 , CdI 2 and CF 3 CO 2 Ag, Burton obtained practically quantitatively the corresponding zinc, silver and cadmium reagents, which were next functionalised in alkylation, arylation, halogenation and oxidative coupling reactions. [21] Our attempts at lithiation of compound 2b and further conversion of the lithiated enamine into the desired derivatives failed. It was difficult to characterise the reaction mixtures or the mixtures with total decomposition of the fluorinated substrate.…”

Fluorinated Organozinc Reagents

“…With a substituted allyl halide, the 2-propenyl reagent gave products of both α-and γ -attack. The predominant product is derived from attack at the less hindered position (equation 64) 5 . …”

Coupling routes to hexafluoro-1,3-butadiene, substituted-1,3-fluorine-containing butadienes and fluorinated polyenes

“…This reaction was extremely exothermic, and although 1 was obtained in low yield, the procedure was not easily scaled up. Later, Morken modified his CuBr 2 procedure for the coupling of the pentafluoropropenyl-2-zinc reagent [33] to the coupling of the trifluorovinylzinc reagent with CuBr 2 .…”

“…Low yields, cyclization by-products and the use of toxic or expensive reagents plagued these previous reports. In a preliminary report, Morken described the preparation of 2,2-dibromohexafluoropropane and its facile conversion to the perfluoropropenyl-2-zinc reagent (4) [33,41]. He found that 4 could be readily converted to 3 via reaction with either CuBr 2 or FeCl 3 (16) [33] (Eq.…”