Oxidative cyclization of 3-oxopropanenitriles with α,β-unsaturated amides by manganese(III) acetate. Regio- and stereoselective synthesis of 4-cyano-2,3-dihydrofuran-3-carboxamides

Chemoselective syntheses of spirodihydrofuryl and spirocyclopropyl barbiturates via cascade reactions of barbiturate-based olefins and acetylacetone

The Michael addition initiated ring closure reaction of barbiturate-based olefins and acetylacetone with NBS has been explored. The efficient and chemoselective approach for the synthesis of barbiturate-fused spirocycles was established. Spirodihydrofuryl barbiturates and spirocyclopropyl barbiturates were synthesized selectively via cascade reactions under different basic conditions in moderate to excellent yields. The structure of 2-(4-chlorophenyl)-1,1-diacetyl-5,7-dimethyl-5,7-diazaspiro[2,5]octane-4,6,8-trione was confirmed by single crystal X-ray diffraction analysis.

DBU-Mediated Addition of α-Nitroketones to α-Cyano-enones and α,β-Unsaturated α-Ketoesters: Synthesis of Dihydrofurans and Conjugated Dienes

1,8-Diazabicyclo[5.4.0]undec-7-ene-mediated reactions of α-nitroketones with α-cyano-enones and α,β-unsaturated α-ketoesters have been developed. The products, namely, dihydrofurans and conjugated dienes, were isolated in moderate to good yields, and a range of substitutions were tolerated.

Copper-mediated tandem reaction of β-ketoesters/ketones with tertiary amines for the synthesis of 2,3-dihydrofurans

A novel synthetic method of 2,3-dihydrofuran using β-ketoester and TMEDA as starting materials has been developed.

Synthesis of dihydrofuro- and C-alkenylated naphthoquinones catalyzed by manganese(III) acetate

The easily synthesis of dihydrofuronaphthoquinones and C-alkenylated naphthoquinones has been investigated through the radical oxidative cyclization of 2-hydroxy-1,4-naphthoquinones and thiophene or furan substituted alkenes catalyzed by manganese(III) acetate.

Zinc-Mediated Facile Synthesis of α,β-Unsaturated Primary Amides

A general method for the synthesis of α,β-unsaturated primary amides was achieved by an one-pot, triphenylphosphine- and zinc powder-promoted Wittig reaction of bromoacetamide and aldehydes under solvent-free conditions.

Studies with beta-oxoalkanonitriles: simple novel synthesis of 3-[2,6-diaryl-4- pyridyl]-3-oxopropanenitriles

Heteroaromatization of ethyl 2-cyano-4-oxo-2-(2-oxo-2-arylethyl)-4-aryl-butanoates 3a,b with ammonium acetate gave ethyl 2,6-diarylisonicotinates 4a,b.Treatment of the latter with acetonitrile afforded novel β-oxoalkanonitriles 6a,b. Reactions of 6a,b with phenyl hydrazine and hydroxylamine gave the corresponding pyridyl aminopyrazoles 8a,b and pyridyl aminoisoxazoles 10a,b, respectively.