Donor-acceptor cyclopropanes are reacted under the influence of a Lewis acid with hydrazonyl chlorides to afford tetrahydropyridazines. Formally, this transformation can be regarded as a [3 + 3]-cycloaddition of three-membered rings and nitrile imines generated in situ. This efficient method provides fast access to a variety of structurally diverse pyridazine derivatives. The structure of a typical product was confirmed by X-ray crystallography.

The first ring-opening reaction of donor-acceptor cyclopropanes to give diamines is reported. For this reaction, a 1,3-bisfunctionalization was developed using cyclopropanes, triazinanes, and Sc(OTf) as the catalyst, followed by treatment with acid. The reaction proceeds under very mild conditions and tolerates many functional groups. Moreover, a library of various 1,3-diazepanes, which arise as intermediates of the first formal aza-[4+3]-cycloaddition reaction with donor-acceptor cyclopropanes, was synthesized.

Donor-acceptor cyclopropanes are reacted with iodobenzene dichloride to afford ring-opened products bearing chlorine atoms in the 1- and 3-positions, adjacent to the donor and acceptor groups. A variety of different donors (e.g., alkyl, aryl, N, and O) and acceptor moieties (e.g., ketones, diesters, and dinitriles) are used.

Palladium-catalyzed activation of carbon-sulfur bonds allows aryne insertion into aryl thiocyanates to generate new C-SAr and C-CN bonds in one step. The readily available starting materials make this method efficient in generating a variety of 1,2-thiobenzonitriles. By choosing an oxygen atmosphere the yields are increased and side reactions are minimized.

Homologation of readily available α‐boryl pyrrolidines with metal carbenoids is especially challenging even when good leaving groups (Cl−) are employed. By performing a solvent switch from Et2O to CHCl3, efficient 1,2‐metalate rearrangement of the intermediate boronate occurs with both halide and ester leaving groups. The methodology was used in the total synthesis of the Stemona alkaloid (−)‐stemaphylline in just 11 steps (longest linear sequence), with high stereocontrol (>20:1 d.r.) and 11 % overall yield. The synthesis also features a late‐stage lithiation–borylation reaction with a tertiary amine containing carbenoid.