An expeditious synthetic route to 1,1-disubstituted indenes from propargyl alcohols and organoboronic acids was developed under rhodium catalysis, and selective 1,4-rhodium migration over β-oxygen elimination was involved as the key step. DPEphos was found to be crucial to promote the transformation, and density functional theory (DFT) calculations indicated that DPEPhos can lower the relative energy of the key intermediate on the 1,4-migration path, leading to the unusual selectivity.

The enantioselective synthesis of a series of C2‐symmetric 3,3′‐diarylated 1,1′‐spirobiindane‐7,7′‐diols (3,3′‐diaryl‐SPINOLs) was developed by sequential Rh‐catalyzed twofold asymmetric conjugate arylation/BF3‐promoted diastereoselective spirocyclization (>20:1 d.r. and >99 % ee for all examples). Some phosphoramidite ligands were prepared from the 3,3′‐Ph‐SPINOL and applied to several catalytic asymmetric reactions, and the 3,3′‐diarylated ligands showed higher enantioselectivities than the privileged nonsubstituted ligands.

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The enantioselective synthesis of chiral azaarenes by rhodium‐catalyzed asymmetric conjugate addition of organoboronic acids to carbonyl‐activated alkenyl azaarenes was reported. Diverse chiral azaarenes were produced in up to 99% yield and with up to 99% ee (>60 examples). Catalytic asymmetric syntheses of dexchlorpheniramine and dexbrompheniramine were realized by using the developed method.magnified image

A chemodivergent synthesis of two series of spirochromans depending on the catalytic system was developed. Starting from diarylideneacetones and organoboronic acids, asymmetric rhodium catalysis led to the enantioselective synthesis of 4,4′-disubstituted 2,2′-spirobichromans, while acid catalysis led to the formation of 4-substituted spirochroman-2,2′-chromenes. A plausible mechanism of the chemodivergent synthesis was proposed.