Digitization of multistep organic synthesis in reactionware for on-demand pharmaceuticals

Chemical manufacturing is often done at large facilities that require a sizable capital investment and then produce key compounds for a finite period. We present an approach to the manufacturing of fine chemicals and pharmaceuticals in a self-contained plastic reactionware device. The device was designed and constructed by using a chemical to computer-automated design (ChemCAD) approach that enables the translation of traditional bench-scale synthesis into a platform-independent digital code. This in turn guides production of a three-dimensional printed device that encloses the entire synthetic route internally via simple operations. We demonstrate the approach for the γ-aminobutyric acid receptor agonist, (±)-baclofen, establishing a concept that paves the way for the local manufacture of drugs outside of specialist facilities

3D designed and printed chemical generators for on demand reagent synthesis

Modern science has developed well-defined and versatile sets of chemicals to perform many specific tasks, yet the diversity of these reagents is so large that it can be impractical for any one lab to stock everything they might need. At the same time, isssues of stability or limited supply mean these chemicals can be very expensive to purchase from specialist retailers. Here, we address this problem by developing a cartridge -oriented approach to reactionware-based chemical generators which can easily and reliably produce specific reagents from low-cost precursors, requiring minimal expertise and time to operate, potentially in low infrastructure environments. We developed these chemical generators for four specific targets; transition metal catalyst precursor tris(dibenzylideneacetone)dipalladium(0) [Pd2(dba)3], oxidising agent Dess-Martin periodinane (DMP), protein photolinking reagent succinimidyl 4,4’-azipentanoate (NHS-diazirine), and the polyoxometalate cluster {P8W48}. The cartridge synthesis of these materials provides high-quality target compounds in good yields which are suitable for subsequent utilization

An autonomous portable platform for universal chemical synthesis

Robotic systems for synthetic chemistry are becoming more common, but they are expensive, fixed to a narrow set of reactions, and must be used within a complex laboratory environment. A portable system that could synthesize known molecules anywhere, on demand, and in a fully automated way, could revolutionize access to important molecules. Here we present a portable suitcase-sized chemical synthesis platform containing all the modules required for synthesis and purification. The system uses a chemical programming language coupled to a digital reactor generator to produce reactors and executable protocols based on text-based literature syntheses. Simultaneously, the platform generates a reaction pressure fingerprint, used to monitor processes within the reactors and remotely perform a protocol quality control. We demonstrate the system by synthesizing five small organic molecules, four oligopeptides and four oligonucleotides, in good yields and purities, with a total of 24,936 base steps executed over 329 h of platform runtime

Carboxylic Group-Assisted Proton Transfer in Gold-Mediated Thiolation of Alkynes

Combined experimental and theoretical studies revealed a complex mechanistic picture in which the carboxylic group-assisted proton transfer from acetic acid to an alkyne molecule is the key step in the unique gold-mediated alkyne transformation that leads to the formation of <i>gem</i>-disubstituted vinyl gold complexes. The structures of the complexes were unambiguously established using NMR spectroscopy (in solution) and X-ray diffraction (in the solid state). ESI-MS study of the reaction mixture revealed multiple gold-containing complexes and clusters. Investigation of the MS² fragmentation patterns of the selected ions suggested the involvement of gold acetylides in the transformation. Further treatment of the complexes with protic acid led to the discovery of a novel route for the gold-mediated alkyne hydrothiolation

Carboxylic Group-Assisted Proton Transfer in Gold-Mediated Thiolation of Alkynes

Combined experimental and theoretical studies revealed a complex mechanistic picture in which the carboxylic group-assisted proton transfer from acetic acid to an alkyne molecule is the key step in the unique gold-mediated alkyne transformation that leads to the formation of <i>gem</i>-disubstituted vinyl gold complexes. The structures of the complexes were unambiguously established using NMR spectroscopy (in solution) and X-ray diffraction (in the solid state). ESI-MS study of the reaction mixture revealed multiple gold-containing complexes and clusters. Investigation of the MS² fragmentation patterns of the selected ions suggested the involvement of gold acetylides in the transformation. Further treatment of the complexes with protic acid led to the discovery of a novel route for the gold-mediated alkyne hydrothiolation

Catalytic Adaptive Recognition of Thiol (SH) and Selenol (SeH) Groups Toward Synthesis of Functionalized Vinyl Monomers

An unprecedented sustainable procedure was developed to produce functionalized vinyl monomers H₂CC­(R)­(FG) starting from a mixture of sulfur and selenium compounds as a functional group donor (FG = S or Se). The reaction serves as a model for efficient utilization of natural resources of sulfur feedstock in oil and technological sources of sulfur/selenium. The catalytic system is reported with amazing ability to recognize SH/SeH groups in the mixture and selectively incorporate them into valuable organic products via wastes-free atom-economic reaction with alkynes (HCCR). Formation of catalyst active site and the mechanism of the catalytic reaction were revealed by joint experimental and theoretical study. The difference in reactivity of μ₁- and μ₂-type chalcogen atoms attached to the metal was established and was shown to play the key role in the action of palladium catalyst. An approach to solve a challenging problem of dynamically changed reaction mixture was demonstrated using adaptive tuning of the catalyst. The origins of the adaptive tuning effect were investigated at molecular level and were found to be governed by the nature of metal–chalcogen bond

A chemically powered unidirectional rotary molecular motor based on a palladium redox cycle

The conversion of chemical energy to drive directional motion at the molecular level allows biological systems, ranging from subcellular components to whole organisms, to perform a myriad of dynamic functions and respond to changes in the environment. Directional movement has been demonstrated in artificial molecular systems, but the fundamental motif of unidirectional rotary motion along a single-bond rotary axle induced by metal-catalysed transformation of chemical fuels has not been realized, and the challenge is to couple the metal-centred redox processes to stepwise changes in conformation to arrive at a full unidirectional rotary cycle. Here, we present the design of an organopalladium-based motor and the experimental demonstration of a 360° unidirectional rotary cycle using simple chemical fuels. Exploiting fundamental reactivity principles in organometallic chemistry enables control of directional rotation and offers the potential of harnessing the wealth of opportunities offered by transition-metal-based catalytic conversions to drive motion and dynamic functions