68820-35-9Relevant articles and documents
A novel synthesis of γ,δ-unsaturated aldehydes from α-formyl-γ-lactones
Snowden, Roger L.,Brauchli, Robert,Linder, Simon
experimental part, p. 1216 - 1225 (2011/09/16)
A preparatively useful one-step transformation of γ,γ- disubstituted α-formyl-γ-lactones into trisubstituted γ,δ-unsaturated aldehydes is described, by means of catalytic amounts of either AcOH or AcOEt in the vapor phase over a glass support. A mechanistic rationale is proposed. Copyright
Azidomercurations of alkenes: Mercury-promoted Schmidt reactions
Pearson,Hutta,Fang
, p. 8326 - 8332 (2007/10/03)
Azides bearing a suitably disposed alkene, when treated with either mercuric perchlorate or mercuric trifluoromethanesulfonate, produce bicyclic iminium ions. This new version of the Schmidt reaction proceeds by capture of the mercuronium ion intermediate by the azide to produce an aminodiazonium ion, which suffers a 1,2-shift to give an iminium ion (e.g., 10 → 16 → 17 → 18). Reduction of the iminium ion may then be carried out to produce an amine. Compared to earlier work on the protic acid-promoted intramolecular Schmidt reaction of azido-alkenes, the mercury-promoted Schmidt reaction has several advantages. First, the acid-promoted Schmidt reaction of azido-alkenes requires that the intermediate carbocations be tertiary, allylic, benzylic, or propargylic. The mercury-promoted method has no such limitation; thus even 1,2-disubstituted alkenes may be used. Second, the mercury-promoted method is milder, allowing the presence of acid-sensitive functionality. The protic version, typically employing trifluoromethanesulfonic acid, is limited in its functional group tolerance. Third, whereas carbocation rearrangement is often observed prior to cyclization/rearrangement in the acid-promoted Schmidt reaction, the mercury-promoted method avoids this problem. Fourth, the presence of the mercurio group during the rearrangment may alter the regioselectivity of the 1,2-migration. Finally, the mercury-bearing iminium ions that are the result of the Schmidt reaction were found to be sensitive to protodemercuration, precluding their use in other transformations.
PALLADIUM-CATALYSED REACTION OF VINYLIC HALIDES WITH PRIMARY ALLYLIC ALCOHOLS: REGIO AND STEREOCONTROLLED SYNTHESIS OF 4-ENALS.
Jeffery, Tuyet
, p. 6641 - 6644 (2007/10/02)
Stereodefined γ,δ-unsaturated aldehydes can be prepared with high regio and stereocontrol by palladium-catalysed coupling of vinylic halides with primary allylic alcohols, in the presence of silver carbonate and tetra-n-butylammonium hydrogen sulphate.
