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Green chemistry places an emphasis on safer chemicals, waste reduction, and efficiency. Processes should be optimized with green chemistry at the forefront of decision making, embedded into research at the earliest stage. To assist in this endeavor, we present a spreadsheet that can be used to interpret reaction kinetics via Variable Time Normalization Analysis (VTNA), understand solvent effects with linear solvation energy relationships (LSER), and calculate solvent greenness. With this information, new reaction conditions can be explored in silico, calculating product conversions and green chemistry metrics prior to experiments. The application of this tool was validated with literature case studies. Reaction performance was predicted and then confirmed experimentally for examples of aza-Michael addition, Michael addition, and an amidation. The combined analytical package presented herein permits a thorough examination of chemical reactions, so that the variables that control reaction chemistry can be understood, optimized, and made greener for research and education purposes.

There is ever increasing demand to develop surfactants based on sophorolipids because they are produced by non-pathogenic organisms, biodegradable and less toxic to humans and the environment. Herein, commercially available lactonic sophorolipid was modified via epoxidation of the fatty acid units CC and subsequent ring-opening of the oxirane with poly(ethylene glycol) of vary chain lengths to deliver a novel range of non-ionic sophorolipid-based surfactants. The methods employed for ring-opening reaction lead to a final surfactant synthesis involving heterogeneous catalysis (metal-exchanged montmorillonite), use of a benign solvent (ethyl acetate) and short reaction time (60 minutes). The resulting surfactants were structurally characterised and a prediction of their potential applications achieved using the hydrophilic-lipophilic balance (HLB) concept, foam capacity and stability of the surfactants at 0.25 surfactant solution. This new family of bio-derivable non-ionic surfactants will be useful as wetting and solubilising agents, oil-in-water emulsifiers and detergents.

Three dipolar aprotic solvents were designed to possess high dipolarity and low toxicity: N,N,N′,N′-tetrabutylsuccindiamide (TBSA), N,N′-diethyl-N,N′-dibutylsuccindiamide (EBSA), and N,N′-dimethyl-N,N′-dibutylsuccindiamide (MBSA). They were synthesized catalytically by using a K60 silica catalyst in a solventless system. Their water immiscibility stands out as an unusual and useful property for dipolar aprotic solvents. They were tested in a model Heck reaction, metal–organic framework syntheses, and a selection of polymer solubility experiments in which their performances were found to be comparable to traditional solvents. Furthermore, MBSA was found to be suitable for the production of an industrially relevant membrane from polyethersulfone. An integrated approach involving in silico analysis based on available experimental information, prediction model outcomes and read across data, as well as a panel of in vitro reporter gene assays covering a broad range of toxicological endpoints was used to assess toxicity. These in silico and in vitro tests suggested no alarming indications of toxicity in the new solvents.

Hesperidin and rutin are two sought-after natural flavonoids, traditionally extracted from abundant natural citrus fruits and tea leaves using large amounts of ethanol or methanol solvents. Recent trends in extractions have focused on minimizing the use of solvents and creating simpler cost-effective processes. This study aims to apply the concept of chemical valorization in the context of a circular economy, by using agro-industrial waste and biobased alternatives to traditional solvents, which are of environmental concern. We use minimum amounts of solvent/sample (5 mL/0.25 or 0.5 g) to extract hesperidin and rutin in a single-stage solid-liquid extraction. Thirty individual solvents and HSPiP were applied to find the best solvents/blends for extraction. The type of solvent, sample preparation, maceration time, and extraction temperature were studied. Results showed that the biobased solvent Cyrene is very effective when mildly heated to 65°C (up to 91) or mixed with water. Adding water to Cyrene forms its geminal diol hydrate, this enhances the solubility and extraction of hesperidin and rutin up to ten times than those of the original pure ketone form. Quantitative sustainability metrics from the CHEM21 Toolkit demonstrated that our extraction methodology is environmentally friendly and offers future potential of isolation of other flavonoids.