An Efficient Procedure for the Synthesis of Polysubstituted Pyrroles in an Ionic Liquid

On the mechanisms of precipitation of graphene on nickel thin films

“…5a) has indeed been observed for individual graphene layers, in the case of carbon nanofibres grown with Ni catalyst, [33,34,36] in the case of epitaxy of graphene on Ru(111) [37], and in the nucleation of single-walled carbon nanotubes on Co [38]. The lateral growth that occurs here then recalls again the mechanism observed in multiwall carbon nanotube growth [39][40][41], especially when the metal is in the form of nail-shaped particles, where the surface under the head of the nail delivers the graphene layers, and its body then guides them in the form of nanotube/nanofibres [40,41]. Such a scheme would explain why large graphite flakes ( fig.…”

“…That draining effect of GBs is most probably associated with their migration during annealing. The latter would provide a growth configuration which recalls that found with nanotubes, where the metal leaves the volume it occupied to the growing graphitic planes [40,41]. Thus, the development of graphite flakes is most probably correlated with GB migration.…”

Hexaalkylguanidinium salts as ionic liquids – applications in titanium and aluminium alcoholate assisted synthesis

“…67,68 Several papers have already reported the use of imidazolium-based ionic liquids as reaction media in the Paal-Knorr pyrrole synthesis; [BMIM]BF 4 was used alone 69 or in combination with catalytic bismuth(III) triate, 70 and [BMIM] HSO 4 served as both a solvent and a Brønsted acid. 71 We tried our reusable IL/catalyst system in this reaction type. The condensation of 2,5-hexanedione and benzylamine to give pyrrole 12 (R 1 ¼ Bn) was investigated rst (Scheme 5, Table 11).…”