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Abstract Aziridines are highly valued synthetic targets in organic and medicinal chemistry. The organocatalytic synthesis of such structures with broad substrate scope and good diastereoselectivity, however, is rare. Herein, we report a broadly applicable and diastereoselective synthetic method for the synthesis oftrans‐aziridines from imines and benzylic or alkyl halides utilizing sulfenate anions (PhSO^–) as the catalyst. Substrates bearing heterocyclic aromatic groups, alkyl, and electron‐rich and electron‐poor aryl groups were shown to be compatible with this method (33 examples), giving good yields and high diastereoselectivities (trans:cis>20 : 1). Further functionalization of aziridines containing cyclopropyl or cyclobutyl groups was achieved through ring‐opening reactions, with a cyclobutyl‐substituted norephedrine derivative obtained through a four‐step synthesis. We offer a mechanistic proposal involving reversible addition of the deprotonated benzyl sulfoxide to the imine to explain the hightrans‐diastereoselectivity. 

Abstract BulkyN,N’‐bidentate ligands can furnish catalysts with enhanced catalytic activity compared to commercially available ligands. Straightforward methods to effectively synthesize a broad range of these ligands, however, are uncommon. In this work, a simple and efficient method is developed for the synthesis of bulkyN,N’‐bidentate ligands, including 2,2’‐bipyridines and enantioenriched pyridine‐oxazolines. The Pd/NIXANTPHOS catalyst system enabled synthesis of a series of bulky 2,2’‐bipyridine‐based ligands and (S)‐pyridine oxazoline‐based enantioenriched ligands with good to excellent yields. The ligands have been benchmarked in the aminofluorination of styrene. magnified image 

Abstract The selenenate anion (RSeO⁻) is introduced as an active organocatalyst for the dehydrohalogen coupling of benzyl halides to formtrans‐stilbenes. It is shown that RSeO⁻is a more reactive catalyst than the previously reported sulfur analogues (sulfenate anion, RSO⁻) and selenolate anions (RSe⁻) in the aforementioned reaction. This catalytic system was also applied to the benzylic‐chloromethyl‐coupling polymerization (BCCP) of a bis‐chloromethyl arene to form ppv (poly(p‐phenylene vinylene))‐type polymers with high yields, M_n(average molecular weight) up to 13,000 and Đ (dispersity) of 1.15. magnified image