Categories: Synthesis of O-Heterocycles >
Synthesis of 2H-pyran-5-ones
Synthetic transformations of the products of the Achmatowicz rearrangement with potassium organotrifluoroborates in the absence of transition metals provide dihydropyranones (2,6-trans), tetrahydropyranones (2,3-cis-2,6-cis) or functionalized 1,4-dicarbonyl compounds depending on the reaction conditions and the substitution pattern. The method has also been adapted for the one-pot synthesis of functionalized pyrroles.
S. Roscales, V. Ortega, A. G. Csák˙, J. Org. Chem., 2018, 83, 11425-11436.
A Pd-catalyzed arylation of Achmatowicz rearrangement products with arylboronic acids provides synthetically versatile C-aryl dihydropyranones under mild conditions.
M. W. Liaw, W. F. Cheng, R. Tong, J. Org. Chem., 2020, 85, 6663-6674.
Lipase B from Candida antarctica catalyzes the oxidative ring expansion of furfuryl alcohols in the presence of aqueous hydrogen peroxide to yield functionalized pyranones under mild conditions. The corresponding piperidinone derivatives can be obtained by a similar enzymatic rearrangement of N-protected furfurylamines.
F. Blume, P. Sprengart, J. Deska, Synlett, 2018, 29, 1293-1296.