The monomers 2-n-butyl-2-oxazoline (BuOx) and 2-n-butyl-2-oxazine (BuOzi) were synthesized following the procedure by Witte and Seeliger. Briefly, in a nitrogen flushed flask, valeronitrile, 3-amino-propanol (for the 2-oxazine synthesis or 2-amino-ethanol for the 2-oxazoline synthesis) and catalytic amounts of zinc acetate dihydrate were mixed and heated to 130 °C for several days and the progress was controlled by 1 H NMR spectroscopy. After completion of the reaction, the mixture was dissolved in dichloromethane and washed three times with H2O. The organic layer was dried with Na2SO4 and concentrated. The raw product was dried with CaH2 and distilled under reduced pressure and nitrogen atmosphere to yield the product as a colourless liquid. Details can be found in the Supporting Information (Figure -S2, Table -S2).