149597-15-9Relevant academic research and scientific papers
Synthesis of fluorinated 1,2,3-butatrienes from α-halovinyl organometallic reagents
Morken,Bachand, Patrick C.,Swenson, Dale C.,Burton, Donald J.
, p. 5430 - 5439 (2007/10/02)
The thermal stability and dimerization reaction of fluorinated α-halovinyl zinc and copper reagents, RR'C=CYM (Y = F, Cl, Br; M = ZnX, Cu), have been explored in detail. Dimerization of these vinyl carbenoids to betatrienes occurred when R was an aromatic (C6H5 or C6F5) and R' was a perfluoroalkyl group (CF3, C2F5, C3F7). The role of the α-halogen was determined; the α-F vinyl copper reagent (R = C6H5, R' = CF3) decomposed by oxidative dimerization to 1,3-dienes while the α-Br and -Cl copper reagents dimerized to butatrienes. The fluorinated butatrienes prepared in this study, (E)- and (Z)-R1R2C==C=C=CR1R2 (R1 = CF3, R2 = C6H5; R1 = C2F5, R2 = C6H5; R1 = n-C3F7, R2 = C6H5; R1 = CF3, R2 = C6F5) are available on a multigram scale and readily obtained with high isomeric purity. The geometry of one member of each isomeric pair of butatrienes was characterized by X-ray crystallography. The mechanism of the dimerization reaction has been determined to be a nucleophilic displacement/β-elimination process. Diels-Alder (1,2-addition), bromination (1,2-addition), and isomerizatioa reactions are described.
