A straightforward and efficient approach to structurally diverse and synthetically useful ring-fluorinated 4H-pyrans via a simple base-mediated cascade reaction of readily available trifluoromethylated alkenes with 1,3-dicarbonyl compounds was developed. The key events of this reaction involve two consecutive C-F substitutions under very mild conditions.

A simple base-mediated tandem SN2'/SNV reaction of the readily available α-trifluoromethyl-α,β-unsaturated carbonyl compounds with N-tosylated 2-aminomalonates was developed, which provide an efficient access to functionalized tetrasubstituted 2-fluoro-2-pyrrolines in good to excellent yields. In contrast, simple 1,2-nucleophilic adducts were produced when α-trifluoromethyl styrenes were used.

The IPrAuNTf2/HNTf2 co-catalyzed cyclization of N-(2-perfluoroalkyl-3-alkynyl) hydroxylamines produces pyrroles in moderate to excellent yield, whereas the AgOTf-catalyzed reaction affords cyclic nitrones in high yields.

A simple base mediated reaction of 2-trifluoromethyl-1,3-conjugated enynes with N-acetylated 2-aminomalonates was developed, which could deliver two distinct types of products depending on substrates, i.e. 4-trifluoromethyl pyrrolidine derivatives, or gem-difluoro-1,3-conjugated enyne derivatives. Various functionalized 4-(difluoromethylene)-1,2,3,4-tetrahydropyridines could be obtained in good yields via the gold(i)-catalysed 6-endo-dig cyclization of the corresponding gem-difluoro-1,3-conjugated enynes under mild conditions.