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An efficient and mild method for the synthesis of functionalized tricyclic 2,3-dihydrofurans, bicyclic 2,3-dihydrofurans, and other tetrasubstituted 2,3-dihydrofurans by domino reaction of 1,3-dicarbonyl compounds and α-bromonitroalkenes with a large substrate scope and excellent diastereoselectivity (only trans isomers) in moderate to excellent yield (up to 96%) has been reported.

A notable temperature effect (nonlinear Eyring plot) on stereoselectivity, trans-configured oxetane 2 versus cis-configured oxetane 2 , is reported in the photochemical [2+2] cycloaddition reaction (Paterno–Buchi reaction) of 2,3-dihydrofuran-3-ol derivatives 1 with benzophenone.

An efficient method was developed for the synthesis of fused dihydroindeno[1,2- b ]furans. One-pot three-component reaction of 1,3-indanedione, aromatic aldehyde and pyridinium ylide in the presence of triethylamine under microwave-irradiation in solvent-free conditions afforded dihydroindeno[1,2- b ]furans in a diastereoselective manner in excellent yields.

Antimony trichloride efficiently catalyses diastereoselective three-component reaction of urea, aromatic aldehydes and 2,3-dihydrofuran or 3,4-dihydro-2H-pyran leading to 4-arylhexahydrofuro[2,3-d]pyrimidin-2(3H)-ones and 4-arylhexahydro-1H-pyrano[2,3-d]pyrimidin-2(8aH)-ones, respectively in good yield.

Palladium-catalysed intermolecular asymmetric Heck reactions were performed on 2,2-diethyl-2,3-dihydrofuran using chiral diphosphine and phosphinamine ligands. The steric effect of increased bulk at the 2-position was examined for phenylations and cyclohexenylations and lower chemical yields, but similar enantioselectivities were obtained compared to the 2,2-dimethyl analogue. The optimum ee for phenylation was 94% and for cyclohexenylation was 93%, both obtained with the t-Bu-substituted diphenylphosphinoaryloxazoline ligand.

The palladium catalysed asymmetric cyclohexenylation of 2,2-dimethyl-2,3-dihydrofuran is described. Use of this substrate allowed for an easy and direct comparison of a range of ligands in this reaction. The ligands employed included BINAP and phosphinamines and enantioselectivities of up to 97% were obtained with tert-leucinol-derived diphenylphosphinoaryloxazolines.

2,2-Dimethyl-2,3-dihydrofuran is tested as a new substrate for the intermolecular asymmetric Heck reaction. Phenylation proceeded in enantioselectivities of up to 98% ee with Pd 0 complexes of diphenylphosphinoferrocenyloxazoline ligands.

The Lewis acid-promoted ene reaction of 3-methylene-2,3-dihydrofuran, 1, with aldehydes gives the corresponding alcohols in good to excellent yield.

Palladium was used for a cross coupling of 2,6-dichloro-3-iodoimidazo[1,2-a]pyridine (2) to 2,3-dihydrofuran (3). Optimization of the coupling conditions have given exclusively (+/−)-2,6-dichloro-3-(2′,5′-dihydrofuran-2′-yl)imidazo[1,2-a]pyridine (4) in high yield. Compound 4 was dihydroxylated using a catalytic amount of osmium tetroxide to give the erythrofuranosyl C-nucleoside derivatives 6 and 7. This is the first report of a C-nucleoside derivative containing a sugar moiety attached to the C3 position of an imidazo[1,2-a]pyridine heterocycle.

The unexpected formation of 3-methylene-2,3-dihydrofuran 1 using the Huang-Minlon modification of the Wolff-Kishner reduction of 3-furaldehyde is discribed. Furan 1 readily undergoes ene reactions with simple electron-deficient alkenes.