80921-72-8Relevant academic research and scientific papers
An expedient route to substituted furans via olefin cross-metathesis
Donohoe, Timothy J.,Bower, John F.
supporting information; experimental part, p. 3373 - 3376 (2010/08/05)
The olefin cross-metathesis (CM) reaction is used extensively in organic chemistry and represents a powerful method for the selective synthesis of differentially substituted alkene products. Surprisingly, efforts to integrate this remarkable process into strategies for aromatic and heteroaromatic construction have not been reported. Such structures represent key elements of the majority of small molecule drug compounds; methods for the controlled preparation of highly substituted derivatives are essential to medicinal chemistry. Here we show that the olefin CM reaction, in combination with an acid cocatalyst or subsequent Heck arylation, provides a concise and flexible entry to 2,5-di- or 2,3,5-tri-substituted furans. These cascade processes portend further opportunities for the regiocontrolled preparation of other highly substituted aromatic and heteroaromatic classes.
Ruthenium-catalysed conversion of 1,4-alkynediols into pyrroles
Pridmore, Simon J.,Slatford, Paul A.,Daniel, Aurélie,Whittlesey, Michael K.,Williams, Jonathan M.J.
, p. 5115 - 5120 (2008/02/09)
Various 1,2,5-substituted pyrroles have been synthesised from 1,4-alkynediols using a ruthenium catalysed isomerisation to give the corresponding 1,4-dicarbonyl compounds, which undergo in situ cyclisation to pyrroles in the presence of amine.
The stereochemistry of the vinylogous Peterson elimination
Fleming, Ian,Morgan, Ian T.,Sarkar, Achintya K.
, p. 2749 - 2763 (2007/10/03)
Base-induced eliminations of the vinylogous β-hydroxysilanes 7, 9, 11 and 12 are stereospecifically syn, giving largely the trans,trans-diene 8 from 7 and 11, the cis,trans-diene 10 from 9, and the trans,cis-diene 13 from 12. When a cis double bond is produced, it is selectively placed adjacent to the carbon atom that originally carried the hydroxy group. E2′ Reactions with silyl as the electrofugal group and acetate as the nucleofugal group, initiated by fluoride ion, are not stereospecific, but can be highly stereoselective in favour of the trans,trans-diene 8 when the carbon substituent at the silicon-bearing end is a cyclohexyl group and the double bond is cis, and in favour of the trans,cis-diene 13 when the carbon substituent at the silicon-bearing end is a methyl group and the double bond is trans. Attempts to use the Peterson reactions to make o-quinodimethanes stereospecifically failed, with no evidence of 1,4-elimination from the alcohols 40 and 41. The corresponding E2′ reaction from the esters using fluoride ion on the acetates or formates 46 and 47 gave stereoselectively the E,E-quinodimethane 48.
α,β-UNSATURATED KETONES IN SUBSTITUTIVE ADDITION WITH 2-ALKYLFURANS AND SOME TRANSFORMATIONS OF THE REACTION PRODUCTS
Akhmedov, Sh. T.,Sadykhov, N. S.,Akhmedova, R. Sh.,Zefirov, N. S.
, p. 1158 - 1161 (2007/10/02)
The substitutive addition of cyclic α,β-unsaturated ketones with 2-alkylfurans proceeds in the presence of catalytic amounts of sulfuric acid to give the corresponding furyl ketones.The latter were converted by Kishner reduction to cycloalkylfurans and were also converted to ethyleneketals, which form adducts with maleic anhydride.
