1 Continuous-flow setups 1.1 Generalities 1.1.1 Pumps Chemyx Nexus 3000 and Chemyx Nexus 6000 syringe pumps were used to handle the feed solutions of tetrabutylammonium azide (nBu4NN3), tosyl chloride (TsCl), p-toluenesulfonyl azide (TsN3), methyl phenylacetate (2a) and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in NMP, methyl phenyldiazoacetate (4a), N-Boc piperidine (3a) and Rhodium(II) octanoate dimer (Rh2(oct)4) in hexane, 4-methyl-N’-(2-oxo-1-phenyl-2-(piperidin-1-yl)ethylidene)benzene sulfono-hydrazide (3b), DBU and Aliquat® 336 in toluene and HCl in ether/methanol or dioxane/methanol. The feed solutions were loaded in Chemyx® stainless steel 5 or 20 mL syringes equipped with DupontTM Kalrez® SpectrumTM AS-568 o-rings (0.239 x 0.070” or 0.549 x 0.103”).
ThalesNano® micro HPLC pumps (0.01 – 10 mL min-1 , max 80 bar, wetted parts: SS 316, ruby and sapphire) were utilized to inject the extraction solvents (10 wt% and 15 wt% aqueous sodium chloride and hexane) and the feed solutions of 4-methyl-N’-(2-oxo-1- phenyl-2-(piperidin-1-yl)ethylidene)benzene sulfonohydrazide (3b), DBU and Aliquat® 336 in toluene for the mesoscale experiments (Corning® Advanced-FlowTM Low-Flow reactor).
A FUJI TechnologiesTM pump (triplex plunger pump HYM-08) was utilized to handle the feed solutions of 4-methyl-N’-(2-oxo-1-phenyl-2-(piperidin-1-yl)ethylidene)benzene sulfonohydrazide (3b), DBU and Aliquat® 336 in toluene for the mesoscale experiments (Corning® Advanced-FlowTM G1 reactor).