Mesoscale Flow Chemistry:  A Plug-Flow Approach to Reaction Optimisation

Abstract

In recent years, chemistry in flowing systems has become more prominent as a method of carrying out chemical transformations, ranging in scale from analytical-scale (microchemistry) through to kilogram-scale synthesis (macrochemistry). The advantages are readily apparentincreased control of conditions leading to greater reproducibility, scaleability, and increased safety/reduced lossalthough its acceptance as a viable synthesis technique has been limited due to its drawbacks, primarily precipitation, liquid handling, and diffusion of the reaction within the reactor. Here, we present details of a system which bridges the gap between micro- and macroreactors and has enabled fast reaction optimisation (using small amounts of reagents) and subsequent multigram scale-up using a commercial reactor.

Heterogeneous Catalytic Hydrogenation Reactions in Continuous‐Flow Reactors

“…It is remarkable that the benzyloxy group, which is widely employed as a protective group of alcohols, did not undergo hydrogenolysis under these reaction conditions (Scheme 14 a). The Baiker group performed the selective semihydrogenation of dehydroisophytol and phenylacetylene in scCO 2 using a nonporous Pd 81 Si 19 glassy alloy catalyst at 130 bar and 55-86 8C. Investigation on the effect of changing carbon dioxide www.chemsuschem.org pressure, temperature, and hydrogen concentration on selectivity and conversion were also considered.…”

The Use of Copper Flow Reactor Technology for the Continuous Synthesis of 1,4‐Disubstituted 1,2,3‐Triazoles

“…Reaction segments are separated by an immiscible fluorous spacer, perfluoromethyldecalin, that prevents segment diffusion and reaction trailing. [10,11] Using this approach, multiple segments can flow through the reactor at any one time, maximizing the systems efficiency and permitting rapid library development (medicinal chemistry) or reaction optimization (process research).…”

Mikrotröpfchen in Mikrofluidiksystemen: eine Technik für Entdeckungen in der Chemie und Biologie

“…[182,183] Eine ähnliche Tendenz wurde auch bei der Nitrierung von Arenen in einem Zweiphasensystem festgestellt. [184] [186] Mit dem Mikrowellen absorbierenden Perfluormethyldecalin (PFMD) als Trägerphase gelangen auch Suzuki-Miyaura-Kreuzkupplungen und nucleophile Substitutionen in Tröpfchen unter Mikrowellenbestrahlung. [187] 9.…”