Cyclopropane rings are aprominent structural motif in biologically active molecules.E nantio-and diastereoselective construction of cyclopropanes through C À Hactivation of arenes and coupling with readily available cyclopropenes is highly appealing but remains ac hallenge.Adual directinggroup-assisted CÀHactivation strategy was used to realizemild and redox-neutral Rh III -catalyzed CÀHa ctivation and cyclopropylation of N-phenoxylsulfonamides in ah ighly enantioselective,d iastereoselective,a nd regioselective fashion with cyclopropenyl secondary alcohols as ac yclopropylating reagent. Synthetic applications are demonstrated to highlight the potential of the developed method. Integrated experimental and computational mechanistic studies revealed that the reaction proceeds via aR h V nitrenoid intermediate,a nd Noyori-type outer sphere concerted proton-hydride transfer from the secondary alcohol to the Rh = Nb ond produces the observed trans selectivity. Figure 3. Optimized geometries,e nergy differences and ee values of the transitions tates TS3 SS and TS3 RR for the alkene insertion step in the (R)-Rh4-catalyzed cyclopropanation reaction.

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An efficient and practical Rh­(III)-catalyzed redox-neutral [4 + 1] annulation of N-phenoxy amides with α,α-difluoromethylene alkynes has been realized to give direct access to the Z-configured monofluoroalkenyl dihydrobenzo­[d]­isoxazole framework with broad substrate compatibility and good functional group tolerance, which was further enhanced by the late-stage C–H modification of complex bioactive compounds. Subsequent density functional theory calculations revealed that the stereoselective β–F elimination involving an allene species played a decisive role in determining the reaction outcome and such Z-selectivity.

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Multiple heteroatoms-doped carbons with 3D ordered macro/meso-microporous structures have not been realized by simple carbonization of metal-organic frameworks (MOFs). Herein, ordered macroporous phosphorus and nitrogen-doped carbon (M-PNC) is prepared successfully...