ABSTRACT
Pentose dehydration and direct transformation of xylan into furfural were performed in a water-cyclopentyl methyl ether (CPME) biphasic system under microwave irradiation. Heated up between 170 and 190 °C in the presence of Nafion NR50 and NaCl, d-xylose, l-arabinose and xylan gave furfural with maximum yields of 80%, 42% and 55%, respectively. The influence of temperature and reaction time on the reaction kinetics was discussed. This study was also completed by the survey of different reactant ratios, such as organic layer-water or catalyst-inorganic salt ratios. The exchange between proton and cation induced by an excess of NaCl was monitored, and a synergetic effect between the remaining protons and the released HCl was also discovered.
Subject(s)
Furaldehyde/chemical synthesis , Xylans/chemistry , Xylose/chemistry , Catalysis , Fluorocarbon Polymers/chemistry , Furaldehyde/chemistry , Hot Temperature , Microwaves , Molecular Structure , Sodium Chloride/chemistry , Water/chemistryABSTRACT
The asymmetric unit of the title compound, C15H17N5, consists of two mol-ecules in which the dihedral angles between the best planes of the purine ring system (r.m.s. deviations = 0.0060 and 0.0190â Å) and the benzene ring are 89.21â (3) and 82.14â (4)°. The mol-ecules within the asymmetric unit are linked into dimers by pairs of N-Hâ¯N hydrogen bonds. Weak C-Hâ¯π contacts and π-π inter-actions [centroid-centroid = 3.3071â (1)â Å] further connect the mol-ecules into a three-dimensional network.
