Preparation of N-alkylamides of highly methylated (HM) citrus pectin

摘要

N-Alkylamides of highly me thy lated (HM) citr us pectin (DM = 73%) were prepared using he teroge neous amino-de -alkoxylation (aminolysis) with five selected n-alk ylamine s. The reaction was carried out in N,N-dimethylformamide at 8°C (n-buty lamine), 25°C (n-hexylamine), and 45°C (n -octy lamine, n-dode cylamine and n-octadecylamine). All the der ivatives wer e converted into acid for ms by washing with acidic water-ethanol mixture . The products wer e analysed b y organic elemental analysis, diffusion reflectio n FT-IR spectr oscopy and by 13C C P/ MAS NMR. Both FT-IR and NMR spe ctra indicate the pre se nce of alkylamide substituents bound to pe ctin. The deg rees of amida-tio n (DA) of the derivatives and molar and mass re action yields (Ymand Yn) were calculated b ased o n the re sults of ele mental analysis. The DA values of the N-alkylamides were 39–55% that cor responde d to Ynof 54–75%