Propargylic alcohols and their derivatives are important classes of organic compounds that can be easily accessible from terminal alkynes and aldehydes or ketones. They are attractive and have been extensively applied as synthetic intermediates in modern organic synthesis. Recent investigations on the chemistry of propargylic alcohols and their derivatives disclosed a variety of highly efficient Lewis acid-catalyzed cascade reactions based on Meyer−Schuster rearrangement of propargylic alcohols and [3,3] rearrangement of propargylic esters and propargyl vinyl ethers. A tremendous number of structurally versatile enones, carbocycles, and heterocycles have been constructed through these methodologies. These advances, including our recent researches in this field, are summarized in this review.

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The sulfuric acid-promoted cascade cyclization of 2-(3-hydroxyprop-1-ynyl)benzonitriles led to an efficient synthesis of spiro[indene-1,1'-isoindolin]-3'-ones. This class of spiro compounds could also be prepared by the sulfuric acid-catalyzed cyclization of 2-(phenylacryloyl)benzonitriles, which were readily derived from 2-(3-hydroxyprop-1-ynyl)benzamides using trifluoroacetic acid as a catalyst.

A highly efficient and convenient construction of the spiro[indene-benzosultam] skeleton from propargylic alcohols has been developed. The reaction proceeded in a Lewis acid catalyzed cascade process, including the trapping of allene carbocation with sulfonamide, electrophilic cyclization, and intramolecular Friedel-Crafts alkylation. In the presence of NIS or NBS, iodo/bromo-substituted spiro[indene-benzosultam]s could be prepared in excellent yields.

An efficient synthesis of 1,3-/1,1-dialkoxy 1,2-dihydroisoquinolines from o-ethynylbenzacetals and sulfonyl azides via a cascade process combining copper-catalyzed alkyne-azide cycloaddition (CuAAC), Dimroth rearrangement, 1,5-OR shift/1,5-H shift, and 6π-electrocyclic ring closure (6π-ERC) is described. Extension of the produced 1,3-dialkoxy-1,2-dihydroisoquinolines to isoquinolium salts is also disclosed.