A new substrate class for Ni-catalyzed C(sp3) cross-coupling reactions is reported. We show that α-oxy radicals generated from abundant and stable benzylic acetals, TMSCl, and a mild reductant can participate in chemoselective cross coupling with aryl iodides and a vinyl triflate using a 2,6-bis(N-pyrazolyl)pyridine (bpp)-ligated Ni catalyst. The mild, base-free conditions are tolerant of a variety of functional groups on both partners; as such, the reaction represents an attractive C–C bond-forming approach to dialkyl ether synthesis. Characterization of a (bpp)NiCl complex relevant to the proposed catalytic cycle is also described.

A double diastereoselective variant of the nucleophile catalyzed aldol-lactonization (NCAL) process is described. This strategy delivers β-lactone-fused carbocycles with good to excellent diastereoselectivities using cinchona alkaloid catalysts with enantioenriched aldehyde acids, which gave low diastereoselectivity based on substrate control alone. β-Lactone fused tetrahydrofurans are also prepared for the first time via the NCAL process, however diastereoselectivity was only modestly improved when applying double diastereodifferentiation to these systems.

A new substrate class for nickel‐catalyzed C(sp3) cross‐coupling reactions is reported. α‐Oxy radicals generated from benzylic acetals, TMSCl, and a mild reductant can participate in chemoselective cross‐coupling with aryl iodides using a 2,6‐bis(N‐pyrazolyl)pyridine (bpp)/Ni catalyst. The mild, base‐free conditions are tolerant of a variety of functional groups on both partners, thus representing an attractive CC bond‐forming approach to dialkyl ether synthesis. Characterization of a [(bpp)NiCl] complex relevant to the proposed catalytic cycle is also described.

Double Diastereoselective, Nucleophile-Catalyzed Aldol Lactonizations (NCAL) Leading to β-Lactone Fused Carbocycles and Extensions to β-Lactone Fused Tetrahydrofurans. -It is demonstrated, that aldol lactonization of ω-carbonyl substituted carboxylic acids with Mukaiyama's reagent can proceed with double diastereodifferentiation. Cinchona alkaloid catalysts can be used to improve the stereoselectivity. -(MORRIS, K. A.; ARENDT, K. M.; OH, S. H.; ROMO*, D.; Org. Lett. 12 (2010) 17, 3764-3767, DOI:10.1021/ol101388h ; Dep. Chem., Tex. A&M Univ., College Station, TX 77842, USA; Eng.) -Mais 51-092

Dialkyl Ether Formation by Nickel-Catalyzed Cross-Coupling of Acetals and Aryl Iodides. -The title ether are chemoselectively obtained by a mild, base-free, and functional-group tolerant C-C bond-forming approach. -(ARENDT, K. M.; DOYLE*, A. G.; Angew. Chem., Int. Ed. 54 (2015) 34, 9876-9880, http://dx.doi.org/10.1002/anie.201503936 ; Dep. Chem., Princeton Univ., Princeton, NJ 08544, USA; Eng.) -Toeppel 50-073