327624-92-0Relevant academic research and scientific papers
Gold(I)-catalyzed rearrangement of alkynloxiranes: A mild access to divinyl ketones
Cordonnier, Marie-Caroline,Blanc, Aurlien,Pale, Patrick
supporting information; experimental part, p. 1569 - 1572 (2009/04/07)
Acyloxylated divinyl ketones are conveniently formed by a new gold(l)-catalyzed rearrangement of (3-acyloxyprop-1-ynyl)oxiranes.
Synthesis of trisubstituted furans from epoxypropargyl esters by sequential SmI2-promoted reduction - Elimination and Pd(II)-catalyzed cycloisomerization
Aurrecoechea,Perez,Solay
, p. 564 - 569 (2007/10/03)
A two-step one-pot synthesis of 2,3,5-trisubstituted furans 8 from 4,5-epoxyalk-2-ynyl esters 6 is described. The sequence is initiated by a SmI2-promoted reduction that takes advantage of the ability of the alkynyloxirane moiety present in 6 to accept electrons from SmI2. The resulting organosamarium species then eliminates an adjacent acetate or benzoate leaving group, leading to the formation of unstable 2,3,4-trien-1-ols 7. Without isolation, these are cycloisomerized to furans 8 by treatment with a catalytic amount of a Pd(II) complex and a proton source. The whole sequence takes place under mild reaction conditions. Some useful functional groups such as cyano and α, βunsaturated esters are tolerated, but benzyl- and silyl-protected hydroxyl groups are deprotected to some extent. Starting materials can be easily assembled using reliable reactions from acetylene, an aldehyde or ketone, and a vinyl halide fragment. This offers the possibility of introducing branched substituents at C-5 of the furan ring.
