61668-33-5Relevant academic research and scientific papers
Reaction des vinylogues d'hemiacetals avec les ethers d'enols β-heterosubstitues : nouvelle synthese et cyclisation de composes δ-dicarbonyles α-heterosubstitues
Poirier, Jean-Marie,Hennequin, Laurent,Fomani, Marie
, p. 436 - 448 (2007/10/02)
Reaction of hemiacetal vinylogs 1 in the presence of boron trifluoride etherate with silyl enol ethers 2 or 3 prepared from α-heterosubstituted ketones 7 or 9 yields α-halo δ-dicarbonyl compounds 4 (X = Cl, Br) or α-methoxy δ-dicarbonyl compounds 5.When s
A New Synthesis of β-Keto Phosphonates and β-Keto Silanes
Sampson, Paul,Hammond, Gerald B.,Wiemer, David F.
, p. 4342 - 4347 (2007/10/02)
A new preparation of β-keto phosphonates from α-bromo ketones, by reaction of dialkyl chlorophosphate electrophiles with the dilithiated derivative of the bromo ketone, is described.This umpolung approach is complementary to the classical Arbuzov synthesis in two important ways.It extends the range of possible ketone substrates, allowing use of secondary α-halo ketones or α-bromo ketones where the Arbuzov reaction often fails.It also extends the variety of phosphonates available, by allowing, for example, the direct preparation of bis-(trifluoroethyl)phosphonates.These fluoroalkyl phosphonates are not readily available via the Arbuzov reaction,because tris(trifluoroethyl) phosphite is only weakly nucleophilic.From our efforts to employ (trialkylsiloxy)vinyl bromides and n-butyllithium to generate an intermediate vinyllithium reagent, in place of forming the lithium enolate and using tert-butyllithium, a facile migration of trialkylsilyl groups from oxygen to the α-carbon has been discovered.This has been exploited in the development of a new route from α-bromo ketones to α-trialkylsilyl ketones.
α-Trialkylsilylketones from α-Bromoketones: Utilization of a 1,3-O to C Silyl Migration
Sampson, Paul,Wiemer, David F.
, p. 1746 - 1747 (2007/10/02)
A new route from α-bromoketones to α-trialkylsilylketones has been developed which demonstrates the viability of halogen-metal exchange vis-a-vis nucleophilic attack at silicon, even with the unhindered trimethylsilyl group.
