282527-11-1Relevant articles and documents
Ring-closing metathesis of allylic O,O- and N,O-acetals
Kinderman, Sape S.,Doodeman, Robin,Van Beijma, Jetze W.,Russcher, Jaap C.,Tjen, Kim C. M. F.,Kooistra, T. Martijn,Mohaselzadeh, Homayun,Van Maarseveen, Jan H.,Hiemstra, Henk,Schoemaker, Hans E.,Rutjes, Floris P. J. T.
, p. 736 - 748 (2007/10/03)
A variety of allylic O,O- and N,O-acetals were synthesized using a mild palladium-catalyzed coupling of an alcohol or sulfonamide with an alkyl or aryl 1,2-propadienyl ether. The resulting linear acetals were used for the synthesis of unsaturated rings via ring-closing metathesis, in which the acetal carbon-a precursor for oxycarbenium or N-sulfonyliminium ions, respectively-served as a reactive center for further introduction of functional groups. The products-unsaturated oxygen and nitrogen heterocyclic scaffolds - offer multiple opportunities for derivatization as illustrated with the synthesis of substituted dihydropyrans, chromenes, enantiopure tetrahydropyridines and an enantiomerically pure quinolizidine amino acid.