The enantioselective construction of axially chiral aryl-naphthopyran skeletons was realized by organocatalytic atroposelective intramolecular [4+2] cycloaddition of in situ generated vinylidene ortho-quinone methides, from 2-ethynylphenol derivatives, with alkynes. Through this method, the heteroatropisomers were obtained with excellent yields and enantioselectivities. Moreover, a speculative model of the stereochemical outcome is proposed based on preliminary mechanistic studies. The products having various functional groups can be easily transformed into valuable intermediates as either potential ligands or organocatalysts.

Organocatalytic selenosulfonylation of the C–C double bond of α,β-unsaturated ketones to construct two contiguous stereogenic centers in an aqueous medium was described. A series of α-selenyl and β-sulfonyl ketones with various functional groups were synthesized in good yields and enantioselectivities with saturated NaCl solution as the solvent. In addition, this protocol had been successfully scaled up to a decagram scale via a simple workup procedure.

An unprecedented highly diastereoselective dimerization of 2-alkynylnaphthols is presented to furnish bridged polycyclic compounds containing a bicyclo[3.2.1]­octane moiety with good to excellent yields. The reaction proceeded under mild conditions using N-iodosuccinimide as a promoter, simultaneously constructing one new C–O bond and two new C–C bonds. A tetra-substituted vinylidene ortho-quinone methide intermediate was likely involved, and the steric hindrance of substituents played a critical role in this transformation.

The enantioselective construction of axially chiral aryl-naphthopyran skeletons was realized by organocatalytic atroposelective intramolecular [4+ +2] cycloaddition of in situ generated vinylidene ortho-quinone methides,from 2-ethynylphenol derivatives,w ith alkynes.T hrough this method, the heteroatropisomers were obtained with excellent yields and enantioselectivities.M oreover,aspeculative model of the stereochemical outcome is proposed based on preliminary mechanistic studies.T he products having various functional groups can be easily transformed into valuable intermediates as either potential ligands or organocatalysts. Scheme 1. Previous work and our strategy.

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