Pentylamine

Butylamine (99 +%), pentylamine (99%), and hexylamine (99%) were purchased from Acros Organics (Morris Plains, NJ, USA). 3,5-dinitrobenzoyl chloride (DNBC) (96.5%), propylamine (98%), tert-Butylamine (99.5%), 4,4′-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) (99%), anhydrous N,N-dimethylacetamide (DMAc) (99.8%), triethylamine (TEA) (99.5%), hydrazine monohydrate (80%), anhydrous pyridine (99.8%), and Pd/C (10%) were purchased from Sigma-Aldrich (Milwaukee, WI, USA). All other reagents and solvents were purchased commercially as analytical grade and used without further purification.

The structure of the product was determined using ¹H and ¹³C NMR spectra. ¹H and ¹³C NMR spectra were recorded on Bruker AV-400 spectrometers (Bruker, Billerica, MA, USA) at 400.13 MHz (¹H) and 100.61 MHz (¹³C) in DMSO-d6. Mass spectra were recorded on a Bruker micrOTOFQ using electrospray ionization (ESI). Silica gel (60–200 mesh, Macherey–Nagel, Düren, Germany) was used for column chromatography; chloroform with gradient of ethanol was used as eluent. Berberine chloride hydrate (TCI Co. (Tokyo, Japan)) was used after oven drying at 95 °C for 5 h. Pentylamine, hexylamine, heptylamine, decylamine, and dodecylamine were purchased from Acros Organics (Geel, Belgium).