Synthesis of 3(2H)-furanone derivatives: p-TsOH/halotrimethylsilane promoted cycloketonization of γ-hydroxyl ynones.

A p-TsOH/halotrimethylsilane facilitated cycloketonization of γ-hydroxyl ynones is detailed. This methodology enables the one-step synthesis of polysubstituted 3(2H)-furanone products. It is remarkable that the reaction exhibits excellent regio- and chemoselectivity by the addition of very small quantities of p-toluenesulfonic acid and water.

Access to Polysubstituted Halophosphorylated Dihydrofurans via Halotrimethylsilane-Promoted Cascade Cyclization of γ-Hydroxyl Ynones with Diphenylphosphine Oxides.

A halotrimethylsilane (TMSX) accelerated cascade halophosphorylation and cycloisomerization of γ-hydroxyl ynones with diphenylphosphine oxides is presented. This methodology allows the one-step synthesis of practical polysubstituted halophosphorylated dihydrofuran derivatives. It is noteworthy that halotrimethylsilane functions as a halogenation reagent as well as a promoter to initiate this transformation. In addition, the reaction system can also be scaled up to gram quantities, and the produced halogenated compounds can undergo further derivatizations by Pd-catalyzed coupling reactions.

Iron(II)-Catalyzed Bisphosphorylation Cascade Cycloisomerization of γ-Hydroxyl Ynones and Diphenylphosphine Oxides: Synthesis of Highly Substituted Bisphosphorylated Dihydrofuran Derivatives.

An iron(II)-catalyzed bisphosphorylation cascade cycloisomerization of readily accessible γ-hydroxyl ynones and diphenylphosphine oxides is described. This strategy provides a variety of valuable polysubstituted bisphosphorylated dihydrofuran scaffolds via the construction of two C-P bonds and one C-O bond within a single procedure. This developed reaction system demonstrates good functional group compatibilities with considerably low catalyst consumption (as low as 1%), which could be further scaled up to gram quantities in satisfactory yields.