The entatic state denotes a distorted coordination geometry of a complex from its typical arrangement that generates an improvement to its function. The entatic-state principle has been observed to apply to copper electron-transfer proteins and it results in a lowering of the reorganization energy of the electron-transfer process. It is ... READ MORE

Allylboronic esters react readily with carbonyls and imines (π-electrophiles), but are unreactive toward a range of other electrophiles. By addition of an aryllithium, the corresponding allylboronate complexes display enhanced nucleophilicity, enabling addition to a range of electrophiles (tropylium, benzodithiolylium, activated ... READ MORE

In order to quantify the electrophilic reactivities of common Michael acceptors, we measured the kinetics of the reactions of monoacceptor-substituted ethylenes (H₂C═CH-Acc, 1) and styrenes (PhCH═CH-Acc, 2) with pyridinium ylides 3, sulfonium ylide 4, and ... READ MORE

The dragonbloodins are a pair of complex flavonoid trimers that have been isolated from the palm tree Daemonorops draco, one of the sources of the ancient resin known as “dragon's blood”. We present a short synthesis that clarifies their relative configurations and sheds light on their origin in Nature. This synthesis features ... READ MORE

Linear free energy relationships, in particular relationships between rate and equilibrium constants, are the basis for our rationalization of organic reactivity. Whereas relationships between the kinetic terms nucleophilicity and nucleofugality and the thermodynamic term basicity have been in the focus of interest for many decades, ... READ MORE

Light induced bond cleavage is an ubiquitous process in large molecules, yet its quantum nature is not fully understood. We present a comprehensive description of the ultrafast light induced CACl bond cleavage in diarylmethyl chlorides combining femtosecond transient absorption measurements with ab initio calculations. We observe a ... READ MORE

The kinetics of the reactions of bis-acceptor-substituted benzyl anions (PhCXY^–, X,Y = CN, CO₂Et, COPh, SO₂Ph) with benzhydrylium ions and quinone methides (reference electrophiles) have been determined in dimethyl sulfoxide solution at 20 °C. The reactions follow second-order kinetics, first order ... READ MORE

The rates of the reactions of the arylsulfonyl-substituted carbanions carrying α-chloro and α-bromo substituents (1a–e) with quinone methides 2a–g and benzylidenemalonates 2h and 2i in DMSO were determined photometrically at 20 °C. The reactions were performed ... READ MORE

The kinetics of the reactions of the vinyl cations 2 [Ph₂C═C⁺–(4-MeO–C₆H₄)] and 3 [Me₂C═C⁺–(4-MeO–C₆H₄)] (generated by laser flash photolysis) with diverse nucleophiles (e.g., pyrroles, halide ions, and ... READ MORE