Solvolysis, Electrochemistry, and Development of Synthetic Building Blocks from Sawdust.

Either aldehyde or cinnamyl ether products can be selectively extracted from raw sawdust by controlling the temperature and pressure of a solvolysis reaction. These materials have been used as platform chemicals for the synthesis of 15 different synthetic substrates. The conversion of the initial sawdust-derived materials into electron-rich aryl substrates often requires the use of oxidation and reduction chemistry, and the role electrochemistry can play as a sustainable method for these transformations has been defined.

Photovoltaic-driven organic electrosynthesis and efforts toward more sustainable oxidation reactions.

The combination of visible light, photovoltaics, and electrochemistry provides a convenient, inexpensive platform for conducting a wide variety of sustainable oxidation reactions. The approach presented in this article is compatible with both direct and indirect oxidation reactions, avoids the need for a stoichiometric oxidant, and leads to hydrogen gas as the only byproduct from the corresponding reduction reaction.

Oxidative cyclization reactions: controlling the course of a radical cation-derived reaction with the use of a second nucleophile.

Construction of new ring systems: Oxidative cyclizations (see picture; RVC=reticulated vitreous carbon) have been conducted that use two separate intramolecular nucleophiles to trap an enol ether-derived radical cation intermediate. The reactions provide a means for rapidly trapping the radical cation intermediate in a manner that avoids competitive decomposition reactions.

Anodic coupling of carboxylic acids to electron-rich double bonds: A surprising non-Kolbe pathway to lactones.

Carboxylic acids have been electro-oxidatively coupled to electron-rich olefins to form lactones. Kolbe decarboxylation does not appear to be a significant competing pathway. Experimental results indicate that oxidation occurs at the olefin and that the reaction proceeds through a radical cation intermediate.

Electrochemical Nickel Catalysis for Sp2-Sp3 Cross-Electrophile Coupling Reactions of Unactivated Alkyl Halides.

A constant-current electrochemical method for reducing catalytic nickel complexes in sp2-sp3 cross-electrophile coupling reactions has been developed. The electrochemical reduction provides reliable nickel catalyst activation and turnover and offers a tunable parameter for reaction optimization, in contrast to more standard activated metal powder reductants. The electrochemical reactions give yields (i.e., 51-86%) and selectivities as high or superior to those using metal powder reductants and provide access to a wider substrate scope.