Selected reactions can be conducted under solventless conditions without the application of metal catalysts.
Sanghamitra Sen, Judit E. Puskas 2015, 'Green Polymer Chemistry: Enzyme Catalysis for Polymer Functionalization', Moleculeshttp://www.mdpi.com/1420-3049/20/5/9358. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)
Solventless mechanochemical synthesis represents a technique with improved sustainability metrics compared to solvent-based processes.
Joseph L. Howard, William Nicholson, Yerbol Sagatov, Duncan L. Browne 2017, 'One-pot multistep mechanochemical synthesis of fluorinated pyrazolones', Beilstein Journal of Organic Chemistryhttps://doi.org/10.3762/bjoc.13.189. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)
Investigated heating conditions showed that the solventless microwave-assisted method gave higher yields of these thioureas.
Nguyen Dinh Thanh 2012, 'Synthesis of Peracetylated β-D-Glucopyranosyl Thioureas from Substituted 2-Aminobenzo-1ʹ,3ʹ-thiazoles', E-Journal of Chemistryhttp://dx.doi.org/10.1155/2012/615601. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)
A solventless synthesis can reduce environmental contamination and can be more convenient than solvent-based synthesis.
Dany Jean -Noël uppiah, Minu Gupta Bhowon, sabina Jhaumeer Laulloo 2009, 'Solventless Synthesis of Imines Derived from Diphenyldisulphide Diamine or p-Vanillin',E-Journal of Chemistryhttp://dx.doi.org/10.1155/2009/636707. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)
Vapor-phase synthesis techniques of polymeric nanostructures offer unique advantages over conventional, solution-based techniques because of their solventless nature.
Alper Balkan, Efe Armagan, Gozde Ozaydin Ince 2017, 'Synthesis of coaxial nanotubes of polyaniline and poly(hydroxyethyl methacrylate)by oxidative/initiated chemical vapor deposition', Beilstein Journal of Nanotechnologyhttps://doi.org/10.3762/bjnano.8.89. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)
This can be accomplished by carrying out the reactions without a solvent in the solventless or solid-state reactions.
Vera M. Kolb 2010, 'On the Applicability of the Green Chemistry Principles to Sustainability of OrganicMatter on Asteroids', Sustainabilityhttp://www.mdpi.com/2071-1050/2/6/1624/. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)