A silver-catalyzed protocol for the synthesis of 3-(1H-isochromen)-chromones is described. The method involves an initial 6-endo-dig cyclization of o-alkynylbenzaldehydes and domino CÀ H alkylation and chromone annulation of the ohydroxyarylenaminones, which enables the installation of 1H-isochromen and chromone in a single structure. This synthetic strategy is advantageous for the excellent regioselectivity, step economy, concise one-pot methodology, gram-scale synthesis, as well as high bond-forming efficiency.

Using benzylamines as the C4 source of 1,4dihydropyridines (1,4-DHPs), a Cu-catalyzed oxidative [1 + 2 + 1 + 2] cascade cyclization for the synthesis of 1,4-DHPs was firstly developed. A broad range of easily available N,Ndimethyl enaminones and benzylamines are employed smoothly to provide a diverse range of 1,4-DHPs with high efficiency. This method is performed by a one-pot cascade C(sp 3 )À H bond functionalization/C(sp 3 )À N cleavage/cyclization strategy to form simultaneously two C(sp 3 )À C(sp 2 ) bonds, two C(sp 2 )À N bonds, and a 1,4-DHP ring.

A transition-metal-free method for the construction of 3-substituted or 3,4-disubstituted quinolines from readily available N,N-dimethyl enaminones and o-aminobenzyl alcohols is reported. The direct oxidative cyclocondensation reaction tolerates broad functional groups, allowing the efficient synthesis of various quinolines in moderate to excellent yields. The reaction involves a C (sp3)-O bond cleavage and a C=N bind and a C=C bond formation during the oxidative cyclization process, and the mechanism was proposed.

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An oxidative [3+2+1] cyclization of enaminones and N‐alkenyl‐2‐pyrrolidinone is described for the synthesis of 4‐alkylated 1,4‐dihydropyridines (1,4‐DHPs). By using terminal olefin as the C4 source of the 1,4‐DHP skeleton, this synthetic strategy provides a series of 1,4‐DHPs through a 1,1‐difunctionalization/cyclization process. In this protocol, two C(sp3)−C(sp2) bonds and a C(sp2)−N bond are simultaneously formed, the hydrogen source on the newly formed methyl group of the 1,4‐DHP skeleton is confirmed and a possible mechanism is proposed.