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We describe a method to generate alkylidene carbenes via tetramethylammonium-fluoride-induced desilylation of silyl vinyl iodides. The reversible carbene generation from an iodovinyl anion enabled us to unearth mechanistic aspects of the trimethylenemethane (TMM) diyl cyclization reaction that could not be explored via previous methods. We observed that a slow diyl-diylophile cycloaddition can induce the reversible formation of an alkylidene carbene from the TMM diyl intermediate via a retro-cyclopropanation at ambient temperature.

Efficient electrocatalytic aziridination of alkenes has been achieved for the first time. A structurally broad range of aziridines was easily accessed using an undivided cell operated at constant current and mediated by a catalytic quantity of n-Bu4NI. The electrocatalytic reaction also proceeded in the absence of additional conducting salt. The aziridination is proposed to follow a radical mechanism.

A new class of metal-free, easy to synthesize redox catalysts based on a triarylimidazole framework is described. With those synthesized thus far, one can access a potential range of ca. 410 mV. They proved to be useful mediators for the activation of benzylic C-H bonds under mild conditions.

[reaction: see text]. A novel approach to simple C-glycosides is reported. Reductive ring opening of 1,2-anhydro sugars with titanocene(III) chloride produces an anomeric radical that can be trapped with a variety of agents. The reaction stereospecifically affords alpha-glycosides and produces a free C-2 hydroxyl group allowing for further elaboration.

[reaction: see text] A novel method for the promotion of Reformatsky-like reactions is presented. The technique employs titanocene(III) chloride as a mild and homogeneous single-electron reductant. The reactions are rapid, operationally simple, and compatible with a wide range of functionalities. These additions are also anti diastereoselective.

[reaction: see text] An expeditious convergent route to the ABC-tricyclic core of the phorbol esters is described. The chemistry capitalizes upon both inter- and intramolecular reductive coupling processes promoted electrochemically and via the use of samarium diiodide.

Intramolecular hydrogen atom transfer to a trimethylenemethane (TMM) diradical has been explored as a route to the antileukemial agent, rudmollin (1).