An iridium‐catalyzed cage B–H sulfonamidation of o‐carborane directed by a carboxylic acid group is reported that proceeds in the absence of ligands or external oxidants. A series of sulfonyl azides can be selectively sulfonamidated at the B(4) site in high yields with excellent functional group tolerance. This approach can also be applied to aryl and aliphatic azides. Innocuous CO2 and N2 were released as byproducts. In addition, the carboxylic acid group can be easily removed under mild conditions.

Av ersatile and efficients trategyf or the total synthesis of the anti-HIV-1 agent concentricolide and its analogues daldinins A, B, and Ch as been established.T his strategy offersamild and facile access to these benzo annulated compounds, bearing multiple stereocenters in good yield with 99% enantiomeric excess (ee)a nd 93% diastereomeric excess( de)v alues. Construction of the corresponding syn dihydrobenzofuran andp hthalide groups can be achieved in one step by Noyoris asymmetric transfer hydrogenation, via dynamic kinetic resolution.

The preparation of cis-2,3-dihydrobenzofuranols with two stereocenters through aqueous asymmetric transfer hydrogenation (ATH) of benzofuranones with the metal catalyst Ru­(II) via dynamic kinetic resolution (DKR) has been developed. A variety of α-alkyl benzofuranones were transformed to obtain optically pure 2,3-dihydrobenzofuran-3-ols with excellent enantioselectivities and acceptable yields under mild conditions.

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