The catalytic intramolecular Wittig reactions of carbonyl‐containing bromides are reported. The R3PO byproducts participate in the catalytic cycle; therefore, the Wittig reaction can be accomplished with only a catalytic amount of organophosphorus reagent. The reaction has also been applied to the efficient and selective synthesis of isoquinolin‐1(2H)‐ones, indoles, 2,3‐dihydro‐1H‐2‐benzazepin‐1‐ones, benzofurans, and 1,2‐dihydroquinolines with a catalytic amount of phosphine oxide (0.1 equiv.) and a tetramethyldisiloxane/titanium isopropoxide [TMDS/Ti(OiPr)4] reductant system (yields: 35–88 %).

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A new efficient DEAD-promoted oxidative Ugi/Wittig reaction for the preparation of 2-(1,2,3,4-tetrahydroisoquinolin-1-yl)­oxazoles has been developed. The one-pot reactions of odorless isocyano­(tri­phenyl­phos­phor­anyl­idene)­acetates, carboxylic acids, and N-aryl-1,2,3,4-tetrahydroisoquinolines produced polysubstituted 2-(1,2,3,4-tetrahydroisoquinolin-1-yl)­oxazoles directly in good yields in the presence of DEAD oxidant.

A robust ligand-free palladium-catalyzed cascade reaction for the synthesis of diversely substituted iminoisoindolinones has been developed. The cascade reaction involves isocyanide insertion into Ugi-3CR adducts, accompanied by unexpected hydroxylation and rearrangement.