260369-59-3Relevant academic research and scientific papers
Ring-closing metathesis of vinyl fluorides towards α-fluorinated α,β-unsaturated lactams and lactones
Marhold, Michael,Stillig, Christian,Fr?hlich, Roland,Haufe, Günter
supporting information, p. 5777 - 5785 (2014/10/15)
Ring-closing olefin metathesis reactions (RCM) using Grubbs II or Hoveyda's catalysts have been applied to a series of N-alkenyl-N-benzyl-α-fluoroacrylamides. α-Fluoro-α,β-unsaturated γ- or δ-lactams incorporating a fluorinated double bond were obtained in moderate to good yields, depending on the nature of substituents on the benzyl ring. The corresponding seven- and eight-membered lactams were not formed under similar conditions. When the N-benzyl group was replaced by an N-tosyl group, the corresponding ε-lactam was also formed in 38% yield. When N-(2-fluoroallyl) derivatives were used instead of fluoroacryloyl derivatives, six-, seven-, and eight-membered N-heterocycles were obtained in low yields. This method was also used to synthesize fluorinated α,β-unsaturated analogues of pyrrolizidine and indolizidine alkaloids from prolinol, and also to synthesize N-benzyl-3-fluoroquinolone in three steps from commercially available 2-vinylaniline in 44% overall yield. Also 3-fluorocoumarin and 3-fluorochromene were prepared from ovinylphenol, and 3-fluoro-benzoxepine was available from o-allylphenol.
Synthesis and reactions of α-fluorovinylphosphonium salts
Hanamoto, Takeshi,Shindo, Keiko,Matsuoka, Miki,Kiguchi, Yasuhide,Kondo, Michio
, p. 103 - 107 (2007/10/03)
The α-fluorovinyltriphenylphosphonium Inflate 4 is prepared in high yields by the diphenylphosphinylation of 1,1-difluoroethylene 1 and subsequent quaternization of the phosphine 2 with diphenyliodonium triflate in the presence of CuCl. The salt 4 then undergoes Michael addition followed by Wittig olefination to give the corresponding monofluoroethylene compounds in good yields. The reaction of 4 with the caesium salts of salicylaldehyde derivatives in DMF at 130 °C affords the corresponding monofluorinated chromenes in a one-pot synthesis. The hydrolysis of 4 in the presence of sodium hydroxide gives triphenylphosphine oxide in quantitative yield. The Royal Society of Chemistry 2000.
